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Regional features of pollen R-values in China

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Science China Earth Sciences 2024年第1期67卷 295-308页

作者： jie xia.Jian NI College of Life Sciences Zhejiang Normal UniversityJinhua 321004China Jinhua Mountain Observation and Research Station for Subtropical Forest Ecosystems Jinhua 321004China

Establishing a quantitative relationship between modern pollen and vegetation remains a pivotal but intricate pursuit within the field of Quaternary *** R-value,a well-established and traditional metric characterized by its simplicity and direct applicability,serves to calibrate the nonlinear disparities between surface pollen and modern *** study entails the construction of a comprehensive pollen R-value dataset for China derived from R-values published between 1987 and *** dataset,compiled after rigorous screening,calibration,and standardization processes,encompasses 898 modern pollen sampling sites and 2115 pollen R-value data entries,encapsulating 152 pollen taxa spanning 65 families and 113 *** the extracted R-values yielded the following insights:(1)A macrospatial analysis validates previously established knowledge at a site-specific ***,pollen R-value variations across China are statistically *** two-thirds of pollen taxa exhibit underrepresentation(e.g.,Taxodiaceae,Corylus,Nitraria,Tamarix,Cyperaceae,Poaceae,and Fabaceae),while the remaining one-third display overrepresentation(e.g.,Pinus,Picea,Betula,Ephedra,Chenopodiaceae,and Artemisia).The degree of underrepresentation surpasses that of overrepresentation,and the representation patterns of Castanea,Quercus,Polygonaceae,and Asteraceae are contingent upon vegetation types.(2)Pollen R-values follow distinct spatial distribution patterns within *** the woody vegetation region of eastern China,R-values progressively decline from north to south,correlating with rising temperatures and ***,in herbaceous vegetation regions of northern and western China,R-values decrease from east to west and from northeast to southwest,corresponding to increased ***,pollen R-values manifest variation contingent on pollen taxa,vegetation types,and climatic regions,even differing for the same taxa across varying

关键词： Pollen R-value Modern pollen-vegetation relationship Regional pattern Variability Paleovegetation reconstruction

维普期刊数据库

Hydrogen-rich surface of MoC catalysts for efficient CO_(2) hydrogenation induced by a coupled hydrogen donator

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Nano Research 2024年第8期17卷 7762-7767页

作者： Dong xu Si-Yuan xia.Qi-Yuan Li jie-Sheng Chen Xin-Hao Li School of Chemistry and Chemical Engineering Frontiers Science Center for Transformative MoleculesShanghai Jiao Tong UniversityShanghai 200240China

Direct CO_(2) hydrogenation offers an important strategy for promoting the global carbon balance,but high thermodynamic and kinetic stability of CO_(2) has restricted its applicability to only a handful of industrial ***,we introduce a proof-of-concept application of the electron-rich Pt surface to promote hydrogen donation for electron-rich MoC particles acting as hydrogen acceptors,thereby constructing hydrogen-rich surface of MoC active ***,the formed hydrogen-rich and electronrich surface could greatly decrease reaction activation energy to boost the efficient CO_(2) hydrogenation into formic acid over the MoC *** optimized MoC@NC/Pt-0.1(NC:nitrogen-doped carbon)catalyst exhibits a high turnover frequency(TOF)value of 1.2 h^(−1) at a lower temperature of 60℃and a TOF of 24.2 h^(−1) under standard reaction conditions widely used in the literature,exceeding 7 times of MoC@NC catalyst and surpassing the benchmark classical non-noble metal active center-based heterogeneous catalyst.

关键词： electron-rich Pt nanoparticles hydrogen donation hydrogen-rich MoC nanoparticles CO_(2) hydrogenation formic acid

Unlocking iron-based mixed-phosphate cathode for sodium-ion batteries through off-stoichiometry

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Nano Research 2024年第9期17卷 8119-8125页

作者： Zhaolu Liu Yongjie Cao Ning Wang Hui Yang Hao Zhang Xinyue xu Nan Wang jie xu Yao Liu Junxi Zhang Yongyao xia Shanghai Key Laboratory of Materials Protection and Advanced Materials in Electric Power Shanghai University of Electric PowerShanghai 200090China Department of Chemistry and Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials Fudan UniversityShanghai 200433China School of Materials Science and Engineering Anhui University of TechnologyMa’anshan 243002China Key Laboratory of Interfacial Physics and Technology Shanghai Institute of Applied PhysicsChinese Academy of SciencesShanghai 201800China

The off-stoichiometric iron-based phosphate(Na_(3.12)Fe_(2.44)(P_(2)O_(7))_(2),denoted as Na3.12)as a low cost and high structure stability cathode material has been widely studied for sodium-ion batteries(SIBs).However,the lower theoretical specific capacity(117 mAh·g^(-1))has seriously limited its practical *** this work,we incorporate varying proportion of sodium-iron phosphate(NaFePO_(4))into the Na3.12 to form a series of new high specific capacity mixed-phosphates Na_(3.12+x)Fe_(2.44+x)(P_(2)O_(7))_(2)(PO_(4))x cathode materials for *** optimizing the introduction amount of NaFePO_(4)into Na_(3.12),the practical reversible of Na_(3.12+x)Fe_(2.44+x)(P_(2)O_(7))_(2)(PO_(4))_(x) increased from 92 to 125.2 mAh·g^(-1).The nano-size Na5.12Fe4.44(P_(2)O_(7))_(2)(PO_(4))_(2) cathode material shows a reversible specific capacity of 125.2 mAh·g^(-1)at 0.1 C in *** at 60 C,it still exhibits a reversible specific capacity of 93.3 mAh·g^(-1)and keeps a capacity retention ratio of 87%after 3000 cycles at 20 ***,we present a novel approach to design a series of off-stoichiometric mixed-phosphates cathode materials for SIBs.

关键词： sodium-ion batteries cathode material iron-based mixed-phosphates off-stoichiometric

Temporal control of the Aux/IAA genes BnIAA32 and BnIAA34 mediates Brassica napus dual shade responses

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Journal of Integrative Plant Biology 2024年第5期66卷 928-942页

作者： Yafei Li Yiyi Guo Yue Cao Pengguo xia.Dongqing xu Ning Sun Lixi Jiang jie Dong Institute of Crop Science College of Agriculture and BiotechnologyZhejiang UniversityHangzhou 310058China Key Laboratory of Plant Secondary Metabolism and Regulation of Zhejiang Province College of Life Sciences and MedicineZhejiang Sci-TechUniversityHangzhou310018China State Key Laboratory of Crop Genetics and Germplasm Enhancement College of AgricultureNanjing Agricultural UniversityNanjing 210095China Key Laboratory of Growth Regulation and Transformation Research of Zhejiang Province School of Life SciencesWestlake UniversityHangzhou 310024China

Precise responses to changes in light quality are crucial for plant growth and *** example,hypocotyls of shade-avoiding plants typically elongate under shade *** this typical shade-avoidance response(TSR)has been studied in Arabidopsis(Arabidopsis thaliana),the molecular mechanisms underlying shade tolerance are poorly *** we report that ***(Brassica napus)seedlings exhibit dual shade *** addition to the TSR,*** seedlings also display an atypical shade response(ASR),with shorter hypocotyls upon perception of early-shade ***-wide selective sweep analysis indicated that ASR is associated with light and auxin ***,genetic studies demonstrated that phytochrome A(BnphyA)promotes ASR,whereas BnphyB inhibits *** ASR,YUCCA8 expression is activated by early-shade cues,leading to increased auxin *** inhibits hypocotyl elongation,as young *** seedlings are highly sensitive to ***,two non-canonical AUXIN/INDOLE-3-ACETIC ACID(Aux/IAA)repressor genes,BnIAA32 and BnIAA34,are expressed during this early ***32 and BnIAA34 inhibit hypocotyl elongation under shade conditions,and mutations in BnIAA32 and BnIAA34 suppress ***,our study demonstrates that the temporal expression of BnIAA32 and BnIAA34 determines the behavior of *** seedlings following shade-induced auxin biosynthesis.

关键词： Brassica napus high-density planting IAA32/34 light signal transduction shade response temporal gene expression

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An efficient data-driven global sensitivity analysis method of shale gas production through convolutional neural network

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Petroleum Science 2024年第4期21卷 2475-2484页

作者： Liang xue Shuai xu jie Nie Ji Qin Jiang-xia.Han Yue-Tian Liu Qin-Zhuo Liao State Key Laboratory of Petroleum Resources and Engineering China University of Petroleum (Beijing) Department of Oil-Gas Field Development Engineering College of Petroleum Engineering China University of Petroleum (Beijing) Chuanqing Drilling Engineering Co.Ltd. China National Petroleum Corporation

The shale gas development process is complex in terms of its flow mechanisms and the accuracy of the production forecasting is influenced by geological parameters and engineering parameters. Therefore, to quantitatively evaluate the relative importance of model parameters on the production forecasting performance, sensitivity analysis of parameters is required. The parameters are ranked according to the sensitivity coefficients for the subsequent optimization scheme design. A data-driven global sensitivity analysis(GSA) method using convolutional neural networks(CNN) is proposed to identify the influencing parameters in shale gas production. The CNN is trained on a large dataset, validated against numerical simulations, and utilized as a surrogate model for efficient sensitivity analysis. Our approach integrates CNN with the Sobol' global sensitivity analysis method, presenting three key scenarios for sensitivity analysis: analysis of the production stage as a whole, analysis by fixed time intervals, and analysis by declining rate. The findings underscore the predominant influence of reservoir thickness and well length on shale gas production. Furthermore, the temporal sensitivity analysis reveals the dynamic shifts in parameter importance across the distinct production stages.

关键词： Shale gas Global sensitivity Convolutional neural network Data-driven

A modern survey method for determining live loads based on multi-source and open-access data on the Internet

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Frontiers of Structural and Civil Engineering 2024年第8期18卷 1135-1147页

作者： Chi xu Jun CHEN jie LI School of Civil Engineering Tongji UniversityShanghai 200092China The State Key Laboratory on Disaster Reduction in Civil Engineering Tongji UniversityShanghai 200092China

Sufficient survey data are required to describe the stochastic behaviors of live ***,due to manual and on-site operation required by traditional survey methods,traditional surveys face challenges like occupant resistance,high costs,and long implementation *** study proposes a new survey method to access live load data online and *** samples are acquired from multi-source,open-access and dynamically updated data on the *** change intervals,geometrical dimensions and object quantities are obtained from transaction information,building attributes and virtual reality models on real estate websites,*** object weights are collected from commodity information on e-commerce *** integration of the aforementioned data allows for the extraction of necessary statistics to describe a live load *** proposed method is applied to a live load survey in China,covering 20040 m^(2),with around 90000 samples acquired for object weights and load *** survey results reveal that about 70%−80%of the amplitude statistics are attributable to 1/6 of the total object types.

关键词： live load online survey method data acquisition data integration

Multiplayer Reach-Avoid Differential Games in 3D Space Inspired by Harris'Hawks'Cooperative Hunting Tactics

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Research 2024年第2期2023卷 41-54页

作者： Wanying Ruan Haibin Duan Yongbin Sun Wanmai Yuan jie xia State Key Laboratory of Virtual Reality Technology and Systems School of Automation Science and Electrical EngineeringBeihang UniversityBeijingChina Peng Cheng Laboratory ShenzhenChina Information Science Academy of CETC BeijingChina

This paper investigates a multiplayer reach-avoid differential game in 3-dimensional(3D)space,which involves multiple pursuers,multiple evaders,and a designated target *** evaders aim to reach the target region,while the pursuers attempt to guard the target region by capturing the *** class of research holds significant practical ***,the complexity of the problem escalates substantially with the growing number of players,rendering its solution extremely *** this paper,the multiplayer game is divided into many subgames considering the cooperation among pursuers,reducing the computational burden,and obtaining numerically tractable strategies for ***,the Apollonius sphere,a fundamental geometric tool for analyzing the 3D differential game,is formulated,and its properties are *** on this,the optimal interception point for the pursuer to capture the evader is derived and the winning conditions for the pursuer and evader are ***,based on the Apollonius sphere,the optimal state feedback strategies of players are designed,and simultaneously,the optimal one-to-one pairings are ***,the Value function of the multiplayer reach-avoid differential game is explicitly given and is proved to satisfy Hamilton-Jacobi-Isaacs(HJI)***,the matching algorithm for the case with pursuers outnumbered evaders is provided through constructing a weighted bipartite graph,and the cooperative tactics for multiple pursuers are proposed,inspired by the Harris'Hawks intelligent cooperative hunting ***,numerical simulations are conducted to illustrate the effectiveness of the theoretical results for both cases where the number of adversary players is equal and unequal between the 2 groups.

关键词： holds satisfy rendering

Evolution of inner wall wrinkle defects in the sinking zone of a thick-walled steel tube during radial forging

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Advances in Manufacturing 2024年第2期12卷 396-408页

作者： Yu-Zhao Yang Cheng xu Li-xia.Fan School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing210094People’s Republic of China

An axia. wrinkle defect was observed in the inner wall of the sinking zone of a thick-wall steel tube processed by cold radial *** can evolve into *** present study focuses on the evolution of wrinkles and the effects of process parameters on them using a three-dimensional radial forging process finite element model,radial forging experiments,and surface morphology *** results indicated that the vertical section angle of the hammer die and the size of the tube blank significantly affect the evolution of *** height-to-width ratioλwas introduced to describe the morphology of *** had an approximately linear relationship with the radius reduction in the sinking *** was a linear correlation between the growth slope ofλand the axia. to circumferential strain ratio|εr/εθ|,which can predict theλunder few process *** the 30SiMn2MoVA steel,at the junction of the forging and sinking zones,the threshold ofλof the wrinkle that can evolve into a fissure is approximately 1.123.

关键词： Radial forging Inner wall Wrinkle defects Evolution Sinking zone

Nanoforming of transferred metal contacts for enhanced twodimensional field effect transistors

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Nano Research 2024年第4期17卷 3210-3216页

作者： Shuoheng xu Zheng Huang jie Guan Yaowu Hu The Institute of Technological Sciences Wuhan UniversityWuhan 430072China School of Power and Mechanical Engineering Wuhan UniversityWuhan 430072China School of Physics Southeast UniversityNanjing 211189China

Two-dimensional transition metal chalcogenides(2D-TMDs)have attracted much attention because of their unique layered structure and physical properties for transistor *** transferred metal contacts on these low-dimensional materials or their homogeneous and heterogeneous multilayers have generated huge interest to avoid deposition *** this paper,we show that there are large physical gaps at both the edge contact and surface contact between the transferred electrodes and the 2D materials.A method called laser shock induced superplastic deformation(LSISD)is proposed to tackle this issue and enhance the performance of the *** enhancement mechanism was investigated by molecular dynamics(MD)simulations of the nanoforming process,atomic force microscopy(AFM),scanning electron microscopy(SEM),transmission electron microscopy(TEM)characterizations of the interfaces,and density functional theory(DFT)*** force effect of laser shock can reduce the contact gap between metals and *** electrical performances of the transistors before and after LSISD,along with MD simulations,are used to find the optimal process *** addition,this paper applies the LSISD method to the short-channel MoS_(2)/graphene vertical transistors to show potential improvement in interface contact and electrical *** paper demonstrates the first report on using mechanical force induced by laser shock to enhance metal–semiconductor interfaces and transistor performances.

关键词： laser shock nanoforming metal-semiconductor contact electronics two-dimensional transistors