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Spatial correlation singularities and orbital angular momentum spectra of partially coherent beams with noncanonical vortex pairs 被引量:1
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作者 MEI Chao CHENG Ke +2 位作者 YI Xiao-wen FU Cai-ying ZENG Ti-xian 《中国光学(中英文)》 北大核心 2025年第5期1243-1254,共12页
By introducing noncanonical vortex pairs to partially coherent beams, spatial correlation singularity (SCS) and orbital angular momenta (OAM) of the resulting beams are studied using the Fraunhofer diffraction integra... By introducing noncanonical vortex pairs to partially coherent beams, spatial correlation singularity (SCS) and orbital angular momenta (OAM) of the resulting beams are studied using the Fraunhofer diffraction integral. The effect of noncanonical strength, off-axis distance and vortex sign on spatial correlation singularities in far field is stressed. Furthermore, far-field OAM spectra and densities are also investigated, and the OAM detection and crosstalk probabilities are discussed. The results show that the number of dislocations of SCS always equals the sum of absolute values of topological charges for canonical or noncanonical vortex pairs. Although the sum of the product of each OAM mode and its power weight equals the algebraic sum of topological charges for canonical vortex pairs, the relationship no longer holds in the noncanonical case except for opposite-charge vortex pairs. The changes of off-axis distance, noncanonical strength or coherence length can lead to a more dominant power in adjacent mode than that in center detection mode, which also indicates that crosstalk probabilities of adjacent modes exceed the center detection probability. This work may provide potential applications in OAM-based optical communication, imaging, sensing and computing. 展开更多
关键词 spatial correlation singularity orbital angular momentum noncanonical vortex partially coherent beam
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Analysis of Temporal and Spatial Variation Characteristics of NDVI in Siziwang Banner and Its Correlation with Meteorological Factors
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作者 Xinyu CHEN 《Meteorological and Environmental Research》 2025年第6期83-85,92,共4页
Based on the data of NDVI and meteorological factors in Siziwang Banner from 2000 to 2021,the temporal and spatial variation characteristics of NDVI in the grassland of Siziwang Banner and its responses to climate cha... Based on the data of NDVI and meteorological factors in Siziwang Banner from 2000 to 2021,the temporal and spatial variation characteristics of NDVI in the grassland of Siziwang Banner and its responses to climate change were analyzed.The results show that the NDVI of grassland in Siziwang Banner tended to rise overall,with the average tendency rate of 0.05/10 a.The annual variation of NDVI was mainly driven by precipitation,and there was an extremely significant positive correlation between the two.During the growing season,temperature was positively correlated with NDVI in May,but then the correlation gradually turned negative.NDVI was generally positively correlated with precipitation,and there was a significant lag. 展开更多
关键词 NDVI Satellite remote sensing Temporal and spatial changes Climate response
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The Interaction Mechanism Between Urban Scale Hierarchy and Urban Networks in China:An Analysis Based on A Spatial Simultaneous Equation Model
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作者 ZHOU Ying ZHENG Wensheng WANG Xiaofang 《Chinese Geographical Science》 2026年第1期19-33,共15页
Owing to intensified globalization and informatization,the structures of the urban scale hierarchy and urban networks between cities have become increasingly intertwined,resulting in different spatial effects.Therefor... Owing to intensified globalization and informatization,the structures of the urban scale hierarchy and urban networks between cities have become increasingly intertwined,resulting in different spatial effects.Therefore,this paper analyzes the spatial interaction between urban scale hierarchy and urban networks in China from 2019 to 2023,drawing on Baidu migration data and employing a spatial simultaneous equation model.The results reveal a significant positive spatial correlation between cities with higher hierarchy and those with greater network centrality.Within a static framework,we identify a positive interaction between urban scale hierarchy and urban network centrality,while their spatial cross-effects manifest as negative neighborhood interactions based on geographical distance and positive cross-scale interactions shaped by network connections.Within a dynamic framework,changes in urban scale hierarchy and urban networks are mutually reinforcing,thereby widening disparities within the urban hierarchy.Furthermore,an increase in a city’s network centrality had a dampening effect on the population growth of neighboring cities and network-connected cities.This study enhances understanding of the spatial organisation of urban systems and offers insights for coordinated regional development. 展开更多
关键词 urban scale hierarchy urban networks spatial interaction spatial spillover effect Baidu migration data spatial simultaneous equation model China
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Suppression of ablative Rayleigh–Taylor instability by spatially modulated laser in inertial confinement fusion
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作者 Zhantao Lu Xinglong Xie +10 位作者 Xiao Liang Meizhi Sun Ping Zhu Xuejie Zhang Chunqing Xing Linjun Li Hao Xue Guoli Zhang Rashid Ul Haq Dongjun Zhang Jianqiang Zhu 《Matter and Radiation at Extremes》 2026年第1期29-38,共10页
The suppression of ablative Rayleigh–Taylor instability(ARTI)by a spatially modulated laser in inertial confinement fusion(ICF)is studied through numerical simulations.The results show that in the acceleration phase ... The suppression of ablative Rayleigh–Taylor instability(ARTI)by a spatially modulated laser in inertial confinement fusion(ICF)is studied through numerical simulations.The results show that in the acceleration phase of ICF implosion,the growth of ARTI can be suppressed by using a short-wavelength spatially modulated laser.The ARTI growth rate decreases as the wavelength of the spatially modulated laser decreases,and ARTI is completely suppressed after a certain wavelength has been reached.A spatially uniform laser is introduced to keep the state of motion of the implosion fluid consistent,and it is found that the proportion of the spatially modulated laser required for complete suppression of ARTI decreases as the wavelength continues to decrease.We also optimize the spatial intensity distribution of the spatially modulated laser.In addition,as the duration of the spatially modulated laser decreases,the proportion required for completely suppressing ARTI increases,but the required energy decreases.When the perturbation wavenumber decreases,the wavelength of the spatially modulated laser required for complete suppression of ARTI becomes longer.In the case of multimode perturbation,ARTI can also be significantly suppressed by a spatially modulated laser,and the perturbation amplitude can be reduced to less than 10% of that without a spatially modulated laser.We believe that the conclusions drawn from our simulations can provide the basis for new approaches to control ARTI in ICF. 展开更多
关键词 ablative Rayleigh Taylor instability ablative rayleigh taylor instability arti numerical simulationsthe spatially modulated laser inertial confinement fusion icf spatially modulated laserthe acceleration phase spatially uniform
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Utilizing Single-cell and Spatial RNA-seq databasE for Alzheimer’s Disease(ssREAD)in hypothesis-driven queries
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作者 Diana Acosta Cankun Wang +1 位作者 Qin Ma Hongjun Fu 《Neural Regeneration Research》 2026年第2期677-678,共2页
Alzheimer’s disease(AD)is the most common form of dementia.In addition to the lack of effective treatments,there are limitations in diagnostic capabilities.The complexity of AD itself,together with a variety of other... Alzheimer’s disease(AD)is the most common form of dementia.In addition to the lack of effective treatments,there are limitations in diagnostic capabilities.The complexity of AD itself,together with a variety of other diseases often observed in a patient’s history in addition to their AD diagnosis,make deciphering the molecular mechanisms that underlie AD,even more important.Large datasets of single-cell RNA sequencing,single-nucleus RNA-sequencing(snRNA-seq),and spatial transcriptomics(ST)have become essential in guiding and supporting new investigations into the cellular and regional susceptibility of AD.However,with unique technology,software,and larger databases emerging;a lack of integration of these data can contribute to ineffective use of valuable knowledge.Importantly,there was no specialized database that concentrates on ST in AD that offers comprehensive differential analyses under various conditions,such as sex-specific,region-specific,and comparisons between AD and control groups until the new Single-cell and Spatial RNA-seq databasE for Alzheimer’s Disease(ssREAD)database(Wang et al.,2024)was introduced to meet the scientific community’s growing demand for comprehensive,integrated,and accessible data analysis. 展开更多
关键词 sex specific alzheimer s disease ad deciphering molecular mechanisms spatial transcriptomics ssread spatial transcriptomics st Alzheimers disease single cell RNA seq
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Correlation between life satisfaction,pleasure level,and negative emotion in patients with chronic renal failure
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作者 Lin-Lin Zhang You-Li Zhang +3 位作者 Ting Liu Jian Wang Chen Chen Xiao-Yu Wang 《World Journal of Psychiatry》 2026年第1期291-298,共8页
BACKGROUND Anxiety,depression,and other negative emotions are common among patients with chronic renal failure(CRF).Analyzing the factors related to negative emotions is necessary to provide targeted nursing care.AIM ... BACKGROUND Anxiety,depression,and other negative emotions are common among patients with chronic renal failure(CRF).Analyzing the factors related to negative emotions is necessary to provide targeted nursing care.AIM To explore the correlations among life satisfaction,pleasure levels,and negative emotions in patients with CRF.METHODS One hundred patients with CRF who received therapy at the First Affiliated Hospital of Jinzhou Medical University between December 2022 and February 2025 were included.The Depression,Anxiety,and Stress Scale(DASS-21),Satisfaction with Life Scale(SWLS),and Temporal Experience of Pleasure Scale(TEPS)were used to evaluate negative emotions,life satisfaction,and pleasure level,respectively.Pearson’s correlation coefficient analyzed the correlation between life satisfaction,pleasure level,and negative emotions.Linear regression analysis identified the factors affecting negative emotions.RESULTS The average DASS-21 score among patients with CRF was 51.90±2.30,with subscale scores of 17.90±1.50 for depression,18.53±1.18 for anxiety,and 15.47±2.36 for stress,all significantly higher than the domestic norm(P<0.05).The average SWLS score was 22.17±4.90.Correlation analysis revealed a negative correlation between the SWLS and total DASS-21 scores(P<0.05),but not with the individual depression,anxiety,or stress dimensions.The average TEPS score was 67.80±8.34.TEPS scores were negatively correlated with the DASS-21 score and the stress dimension(P<0.05),but not with depression or anxiety.Linear regression analysis showed that TEPS scores significantly influenced DASS-21 scores(P<0.05).CONCLUSION Patients with CRF experience high levels of negative emotions,which are negatively correlated with life satisfaction and pleasure.Furthermore,pleasure level had an impact on negative emotions. 展开更多
关键词 Chronic renal failure HEMODIALYSIS Negative emotion Life satisfaction PLEASURE correlation
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Janus effect of inter-orbital hybridization on correlation strength of strongly correlated systems:A dynamical mean-field study
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作者 Jian Sun Yinchang Zhao Chao Lian 《Chinese Physics B》 2026年第2期529-537,共9页
In multi-orbital systems,the correlation strength is typically attributed to Coulomb interactions and Hund's couplings.However,this study demonstrates that on-site inter-orbital hybridization can also significant ... In multi-orbital systems,the correlation strength is typically attributed to Coulomb interactions and Hund's couplings.However,this study demonstrates that on-site inter-orbital hybridization can also significant influence the correlation strength of the system.We investigate the impact of on-site inter-orbital hybridization on the correlation strength of a two-orbital Hubbard model on a square lattice using the dynamical mean-field theory combined with Lanczos exact diagonalization.Our findings reveal a distinct Janus effect:on-site inter-orbital hybridization enhances correlation strength in the non-half-filled regime while suppresses it at half-filling.This dual role of on-site inter-orbital hybridization provides a fundamental mechanism for tuning the strength of correlations in multi-orbital systems. 展开更多
关键词 strongly correlated multi-orbital system inter-orbital hybridization dynamical mean-field theory
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Disorder-induced enhancement of nonclassical correlations in programmable integrated quantum walks
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作者 Zhi-Yuan Zhang Yang Chen +7 位作者 Lan-Tian Feng Jin-Hao Zheng Qin-Qin Wang Bo-Yu Xu Yu-Yang Ding Xiao-Ye Xu Guang-Can Guo Xi-Feng Ren 《Advanced Photonics Nexus》 2026年第1期248-256,共9页
Programmable two-particle quantum walks are crucial for advancing quantum simulation,computation,and information processing.Although disorder is traditionally associated with information loss,it can also facilitate em... Programmable two-particle quantum walks are crucial for advancing quantum simulation,computation,and information processing.Although disorder is traditionally associated with information loss,it can also facilitate emergent phenomena such as enhanced energy transport.Here,we experimentally realize a 12-step discrete-time quantum walk in programmable integrated photonic circuits,introducing tunable static and dynamic disorder to explore quantum transport dynamics.In periodic lattices,disorder induces light localization and drives a transition from quantum ballistic to classical diffusive behavior.In particular,quantum walks of correlated photons exhibit a disorder-induced bunching effect,accompanied by enhanced nonclassical correlations.Our platform provides a scalable framework for investigating multiparticle quantum dynamics in engineered environments,promoting the development of quantum optics toward large-scale applications. 展开更多
关键词 integrated quantum photonics disordered quantum walks SUPERDIFFUSION quantum correlations
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The application and prospects of spatial omics technologies in clinical medical research and molecular diagnostics
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作者 Xiaofeng Wu Weize Xu +4 位作者 Da Lin Leqiang Sun Lit-Hsin Loo Jinxia Dai Gang Cao 《Journal of Genetics and Genomics》 2026年第2期181-196,共16页
While conventional FISH and IHC methods struggle to decode complex tissue heterogeneity and comprehensive molecular diagnosis due to low-throughput spatial information,spatial omics technologies enable high-throughput... While conventional FISH and IHC methods struggle to decode complex tissue heterogeneity and comprehensive molecular diagnosis due to low-throughput spatial information,spatial omics technologies enable high-throughput molecular mapping across tissue microenvironments.These technologies are emerging as transformative tools in molecular diagnostics and medical research.By integrating histopathological morphology with spatial multi-omics profiling(genome,transcriptome,epigenome,and proteome),spatial omics technologies open an avenue for understanding disease progression,therapeutic resistance mechanisms,and precise diagnosis.It particularly enhances tumor microenvironment analysis by mapping immune cell distributions and functional states,which may greatly facilitate tumor molecular subtyping,prognostic assessment,and prediction of the radiotherapy and chemotherapy efficacy.Despite the substantial advancements in spatial omics,the translation of spatial omics into clinical applications remains challenging due to robustness,efficacy,clinical validation,and cost constraints.In this review,we summarize the current progress and prospects of spatial omics technologies,particularly in medical research and diagnostic applications. 展开更多
关键词 spatial omics Multi-omics Molecular diagnostics Clinical medical research Precise medicine
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The measurement of the energy correlations between two^(252)Cf prompt fission neutrons
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作者 Huai-Yong Bai Hang Li +8 位作者 Hong-Jun Zhang Cheng-Guo Pang Ming Su Zhong-Hua Xiong Ji Wen Fan Gao Chen-Guang Li Xiao-Dong Wang Li-Sheng Yang 《Nuclear Science and Techniques》 2026年第4期202-215,共14页
The energy correlations of prompt fission neutrons have not yet been considered in the related coincidence and multiplication measurement techniques.To measure and verify the energy correlations,an experiment was perf... The energy correlations of prompt fission neutrons have not yet been considered in the related coincidence and multiplication measurement techniques.To measure and verify the energy correlations,an experiment was performed with a total measurement duration of approximately 1200 h.In the experiment,eight CLYC detectors and sixteen EJ309 liquid scintillation detectors were utilized,and the fission moment was tagged with the measured fissionγ-rays.The relative ratios of the energy spectra of the neutrons correlated with different energy neutrons to the^(252)Cf fission neutron energy spectra were obtained.The present results may be helpful for studying fission physics and nuclear technology applications. 展开更多
关键词 Energy correlations Prompt fission neutrons Energy spectrum Fissionγ-rays
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Electronic correlations and topological states at the interface of twisted bilayer graphene and chromium oxychloride
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作者 Minsheng Li Zehao Jia +6 位作者 Xiangyu Cao Qiang Ma Chang Jiang Yuda Zhang Linfeng Ai Pengliang Leng Faxian Xiu 《Chinese Physics B》 2026年第2期185-192,共8页
When two layers of graphene are stacked with a twist angle of approximately 1.1°,strong interlayer coupling gives rise to a pair of flat bands in twisted bilayer graphene(TBG),resulting in pronounced electron–el... When two layers of graphene are stacked with a twist angle of approximately 1.1°,strong interlayer coupling gives rise to a pair of flat bands in twisted bilayer graphene(TBG),resulting in pronounced electron–electron interactions.At half filling of the flat bands,TBG exhibits correlated insulating states.Here,we investigate the electrical transport properties of heterostructures composed of TBG and the antiferromagnetic insulator chromium oxychloride(CrOCl),and propose a strategy to modulate the correlated insulating states in TBG.During the transition from a conventional phase to a strong interfacial coupling phase,kink-like features are observed in the charge neutrality point(CNP),correlated insulating state,and band insulating state.Under a perpendicular magnetic field,the system exhibits broadened quantum Hall plateaus in the strong interfacial coupling regime.Electrons localized in the CrOCl layer screen the bottom gate,rendering the carrier density in TBG less sensitive to variations in the bottom gate voltage.These phenomena are well captured by a charge-transfer model between TBG and CrOCl.Our results provide insights into the control of electronic correlations and topological states in graphene moirésystems via interfacial charge coupling. 展开更多
关键词 twisted bilayer graphene correlated insulating state CrOCl interfacial coupling charge transfer
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Spatial response and prediction model for blasting-induced vibration in a deep double-line tunnel
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作者 Chong Yu Yongan Ma +3 位作者 Haibo Li Changjian Wang Haibin Wang Linghao Meng 《International Journal of Mining Science and Technology》 2026年第1期169-186,共18页
Excessive blasting-induced vibration during drilling-and-blasting excavation of deep tunnels can trigger geological hazards and compromise the stability of both the rock mass and support structures.This study focused ... Excessive blasting-induced vibration during drilling-and-blasting excavation of deep tunnels can trigger geological hazards and compromise the stability of both the rock mass and support structures.This study focused on the deep double-line Sejila Mountain tunnel to systematically analyze the spatial response of blasting-induced vibration and to develop a prediction model through field tests and numerical simulations.The results revealed that the presence of a cross passage significantly altered propagation paths and the spatial distribution of blasting-induced vibration velocity.The peak particle velocity(PPV)at the cross-passage corner was amplified by approximately 1.92 times due to wave reflection and geometric focusing.Blasting-induced vibration waves attenuated non-uniformly across the tunnel cross-section,where PPV on the blast-face side was 1.54–6.56 times higher than that on the opposite side.We propose an improved PPV attenuation model that accounts for the propagation path effect.This model significantly improved fitting accuracy and resolved anomalous parameter(k and a)estimates in traditional equations,thereby improving prediction reliability.Furthermore,based on the observed spatial distribution of blasting-induced vibration,optimal monitoring point placement and targeted vibration control measures for tunnel blasting were discussed.These findings provide a scientific basis for designing blasting schemes and vibration mitigation strategies in deep tunnels. 展开更多
关键词 Blasting-induced vibration spatial response Attenuation law Prediction model Double-line tunnel
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A high-definition spatially resolved metabolomics method to illuminate the metabolic specificity and interconnection across mouse brain
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作者 Meng Yu Yanhe Zhou +9 位作者 Guanlin Xiao Xinyi Jiang Xiangyi Wang Tong Li Jianpeng Huang Jiamin Gao Junwen Shi Xiuli Gao Zeper Abliz Jiuming He 《Chinese Chemical Letters》 2026年第1期527-532,共6页
The brain's functions are governed by molecular metabolic networks.However,due to the sophisticated spatial organization and diverse activities of the brain,characterizing both the minute and large-scale metabolic... The brain's functions are governed by molecular metabolic networks.However,due to the sophisticated spatial organization and diverse activities of the brain,characterizing both the minute and large-scale metabolic activity across the entire brain and its numerous micro-regions remains incredibly challenging.Here,we offer a high-definition spatially resolved metabolomics technique to better understand the metabolic specialization and interconnection throughout the mouse brain using improved ambient mass spectrometry imaging.This method allows for the simultaneous mapping of thousands of metabolites at a 30 μm spatial resolution across the mouse brain,ranging from structural lipids to functional neurotransmitters.This approach effectively reveals the distribution patterns of delicate microregions and their distinctive metabolic characteristics.Using an integrated database,we annotated 259 metabolites,demonstrating that the metabolome and metabolic pathways are unique to each brain microregion.The distribution of metabolites,closely linked to functionally connected brain regions and their interactions,offers profound insights into the complexity of chemical processes and their roles in brain function.An initial dataset for future metabolomics research might be obtained from the high-definition mouse brain's spatial metabolome atlas. 展开更多
关键词 AFADESI-MSI spatially resolved metabolomics Metabolic specificity and interconnection Mouse brain
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Spatial morphology optimization for reconciling urban expansion with ecological integrity based on a multi-level ecological network framework
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作者 LU Jie JIAO Sheng CHEN Xingli 《Journal of Geographical Sciences》 2026年第2期399-420,共22页
Urban spatial morphology(USM)optimization is critical to balancing biodiversity conservation and sustainable urbanization.However,previous studies predominantly focused on the socio-economic efficiency and static ecol... Urban spatial morphology(USM)optimization is critical to balancing biodiversity conservation and sustainable urbanization.However,previous studies predominantly focused on the socio-economic efficiency and static ecological metrics and rarely addressed the dynamic USM optimization across spatial scales.Here,we developed a multi-level ecological network(MEN)framework to resolve the tension between urban expansion and ecological integrity.By integrating the cost-weighted distance analysis with a hierarchical network transmission mechanism,we established a cross-scale spatial optimization system,which coordinated the regional ecological corridors and local habitat patches.Comparative experiments with conventional single-scale approaches and scenario simulations using the PLUS model show that the MEN framework had superior performance in three dimensions:(1)spatial governance:the primary-level network(peri-urban natural reserves)effectively contained urban sprawl,and the secondary-level network(intra-urban green corridors)mitigated habitat fragmentation and improved the built-environment;(2)scenario robustness:the model maintained an optimal compactness-loose balance in multiple development pathways;(3)landscape metrics:patch fragmentation decreased by 18.25%,and the internal landscape richness improved by 10.66%compared to the scenario without USM optimization.The findings provide new insight to establish a hierarchical ecological optimization framework as a nature-based spatial protocol to reconcile metropolitan growth with landscape sustainability. 展开更多
关键词 urban spatial morphology ecological network multi-level coupling scenarios simulation urban expansion
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Spatial carbon channel with confined ultrafine nano-phosphides for boosted reversible sulfur redox in lithium-sulfur batteries
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作者 Guanyu Mu Min Hu +4 位作者 Zhaohuang Cai Junwu Xiao Fei Xiao Jiangbo Xi Shuai Wang 《Journal of Energy Chemistry》 2026年第2期126-135,I0004,共11页
Sluggish kinetics coupled with parasitic shuttling reactions are pivotal challenges hindering the performance of lithium-sulfur(Li-S)batteries.Improving areal capacity and cyclability of Li-S batteries can be achieved... Sluggish kinetics coupled with parasitic shuttling reactions are pivotal challenges hindering the performance of lithium-sulfur(Li-S)batteries.Improving areal capacity and cyclability of Li-S batteries can be achieved by addressing these challenges.A composite sulfur host material is synthesized herein by in situ anchoring ultrafine cobalt-iron phosphide nanoparticles(5-7 nm)onto a hollow mesoporous carbon sphere(HMCS)framework.This strategy achieved exceptional spatial restriction and a high density of catalytically active sites through the encapsulation of sulfur within a hollow-structured framework.Specifically,HMCS expedites rapid Li_(2)S nucleation kinetics,while CoFeP facilitates robust Li_(2)S dissolution kinetics by mitigating decomposition barriers.This synergistic integration equips CoFeP@HMCS with robust bi-directional catalytic activity,significantly promoting interracial charge-transfer,facilitate sulfu r multistep catalytic conversion,and inhibiting shuttling.Consequently,the battery exhibits excellent rate performance(991 mA h g^(-1) at 5.0 C)and retains a high areal capacity of 6.06 mA h cm^(-2) after 200 cycles under a high areal sulfur loading of 8.2 mg cm^(-2) but a low electrolyte/sulfur ratio of 4.8μL mg^(-1).This work contributes to enhancing the practical specific capacity of lithium-sulfur batteries and deepens the understanding of catalysts enabling bidirectional electrocatalytic sulfur conversion. 展开更多
关键词 spatial carbon channel Ultrafine nano-phosphides Reversible sulfur redox Lithium sulfur batteries
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Drive-by spatial offset detection for high-speed railway bridges based on fusion analysis of multi-source data from comprehensive inspection train
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作者 Chuang Wang Jiawang Zhan +4 位作者 Nan Zhang Yujie Wang Xinxiang Xu Zhihang Wang Zhen Ni 《Railway Engineering Science》 2026年第1期128-148,共21页
The spatial offset of bridge has a significant impact on the safety,comfort,and durability of high-speed railway(HSR)operations,so it is crucial to rapidly and effectively detect the spatial offset of operational HSR ... The spatial offset of bridge has a significant impact on the safety,comfort,and durability of high-speed railway(HSR)operations,so it is crucial to rapidly and effectively detect the spatial offset of operational HSR bridges.Drive-by monitoring of bridge uneven settlement demonstrates significant potential due to its practicality,cost-effectiveness,and efficiency.However,existing drive-by methods for detecting bridge offset have limitations such as reliance on a single data source,low detection accuracy,and the inability to identify lateral deformations of bridges.This paper proposes a novel drive-by inspection method for spatial offset of HSR bridge based on multi-source data fusion of comprehensive inspection train.Firstly,dung beetle optimizer-variational mode decomposition was employed to achieve adaptive decomposition of non-stationary dynamic signals,and explore the hidden temporal relationships in the data.Subsequently,a long short-term memory neural network was developed to achieve feature fusion of multi-source signal and accurate prediction of spatial settlement of HSR bridge.A dataset of track irregularities and CRH380A high-speed train responses was generated using a 3D train-track-bridge interaction model,and the accuracy and effectiveness of the proposed hybrid deep learning model were numerically validated.Finally,the reliability of the proposed drive-by inspection method was further validated by analyzing the actual measurement data obtained from comprehensive inspection train.The research findings indicate that the proposed approach enables rapid and accurate detection of spatial offset in HSR bridge,ensuring the long-term operational safety of HSR bridges. 展开更多
关键词 High-speed railway bridge Drive-by inspection spatial offset Multi-source data fusion Deep learning
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Uneven gains from agricultural modernization:Spatial spillover effects and regional heterogeneity of grain yield in China’s nine major agricultural zones
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作者 LIANG Jiale PAN Sipei +3 位作者 XIA Nan WANG Zhenkang CHEN Wanxu LI Manchun 《Journal of Geographical Sciences》 2026年第3期575-596,共22页
Ensuring national food security amidst rapid population growth and increasing extreme weather events remains a critical global challenge.However,the extent to which agricultural modernization in China enhances grain y... Ensuring national food security amidst rapid population growth and increasing extreme weather events remains a critical global challenge.However,the extent to which agricultural modernization in China enhances grain yield and contributes to food security remains unclear.Therefore,using panel data from 327 Chinese cities(2013–2021),this study employs spatial econometric models to analyze the spatial spillover effects of agricultural modernization level(AML)on grain yield and to reveal regional heterogeneity across nine major agricultural zones.The results showed a cumulative grain yield increase of 23.7 million tons,with peak productivity concentrated along the Hu Line and declining eastward and westward.AML also exhibited a steady increase but a clear spatial gradient,decreasing from coastal to inland regions,with the highest level observed in Southern China(SC).A key finding was that a 1%increase in AML directly raised local grain yield by an average of 4.185%,accompanied by significant positive spillover effects on neighboring regions.Regional variations revealed distinct patterns:the direct effects of AML were more pronounced in southern and eastern zones,while spillover effects dominated in northern and western zones.The largest positive direct impact of AML on grain yield was observed in the SC(8.499%),while Middle-Lower Yangtze Plain ranked second but exhibited the strongest positive spatial spillover effect(4.534%).These findings highlight the critical role of agricultural modernization in promoting grain production and provide a solid basis for optimizing regional agricultural systems,ensuring food security,and advancing sustainable agriculture. 展开更多
关键词 agricultural modernization grain yield spatial spillover effects nine major agricultural zones China
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Octupole correlations of the K^(π)=5/2^(+)ground-state band in^(229)Th
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作者 Yuan-Yuan Wang Peng-Wei Zhao 《Chinese Physics B》 2026年第2期156-161,共6页
The octupole correlations of the K^(π)=5/2^(+)ground state and the rotational spectrum built on it in^(229)Th are studied using the microscopic relativistic density functional theory on a three-dimensional lattice sp... The octupole correlations of the K^(π)=5/2^(+)ground state and the rotational spectrum built on it in^(229)Th are studied using the microscopic relativistic density functional theory on a three-dimensional lattice space and the reflection-asymmetric triaxial particle rotor model.It is found that^(229)Th has a ground state with static axial octupole and quadrupole deformations.The occurrence of octupole correlations,driven by the octupole deformation,is analyzed through the evolution of single-particle levels around the Fermi surface.The experimental energy spectrum and the electromagnetic transition probabilities,including B(E2)and B(M1),are reasonably well reproduced. 展开更多
关键词 octupole correlation relativistic density functional theory reflection-asymmetric triaxial particle rotor model rotational spectrum
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Spatially biased collections and the failure to cover all wild genetic clusters in plant populations under ex situ conservation
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作者 Zhiqiang Xiao Hui Liu +5 位作者 Guiyun Huang Di Wu Liwen Qiu Jinhua Wu Xinzeng Wei Mingxi Jiang 《Plant Diversity》 2026年第1期75-83,共9页
Successful ex situ conservation of plant populations requires a high degree of genetic representativeness.However,spatially biased sampling in ex situ conservation efforts may fail to capture all wild genetic clusters... Successful ex situ conservation of plant populations requires a high degree of genetic representativeness.However,spatially biased sampling in ex situ conservation efforts may fail to capture all wild genetic clusters for species with range-wide genetic structure.To investigate the extent of spatially biased sampling in living collections and the coverage of wild genetic clusters in plant populations under ex situ conservation worldwide,we combined a global synthesis of ex situ conservation efforts with a case study of an endangered riparian plant species,Myricaria laxiflora.Our analysis of ex situ conservation worldwide revealed that the majority(82.6%)of ex situ populations fail to cover all wild genetic clusters,largely due to spatially biased sampling with low geographic coverage.Our case study of M.laxiflora showed that genetic diversity differed between the ex situ and upstream populations,while it was comparable between ex situ populations and other wild populations.However,current ex situ populations did not cover all wild genetic clusters,as the upstream genetic cluster was previously uncollected.Our study suggests that the failure to cover all wild genetic clusters in ex situ populations is a widespread issue,and ex situ populations with high genetic diversity can also fail to cover all wild genetic clusters.In future ex situ conservation programs,both the importance of high genetic diversity and the high coverage of wild genetic clusters should be prioritized. 展开更多
关键词 Conservation genomics Genetic representativeness Ex situ conservation Genetic composition Geographic coverage spatially biased sampling
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Short-term photovoltaic output prediction based on spatial downscaling NWP data and CNN-iTransformer-LSTM model
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作者 Zhewen Hu Ligang Du +2 位作者 Xin Zhang Lei Zhang Wei Hu 《iEnergy》 2026年第1期71-86,共16页
To enhance the accuracy of short-term photovoltaic power output prediction and address issues such as insufficient spatial resolution of meteorological forecast data and weak generalization ability of models,this pape... To enhance the accuracy of short-term photovoltaic power output prediction and address issues such as insufficient spatial resolution of meteorological forecast data and weak generalization ability of models,this paper proposes a prediction method that integrates spatial downscaling meteorological data with a convolutional neural network(CNN)-iTransformer-long short-term memory(LSTM)model.First,the rime-optimized random forest regression algorithm(RIME-RF)is employed to perform spatial downscaling on numerical weather prediction(NWP)data,thereby improving its local applicability.Second,a CNN-iTransformer-LSTM hybrid prediction model is constructed.This model utilizes a CNN as a spatial feature extractor to capture local patterns in meteorological data,employs an iTransformer to model the global dependencies among multiple variables,and leverages an LSTM to enhance the learning of short-term temporal dynamic features,thereby achieving efficient collaborative mining of multi-scale features.Finally,experiments are conducted using actual data from a photovoltaic power station in Hebei,China,during various seasons and weather conditions.The results show that the proposed model outperforms the comparison models in terms of the root mean square error(RMSE),mean absolute error(MAE),and R2,maintaining high prediction accuracy and stability even under complex weather conditions such as overcast and rainy days.The downscaling process further enhances the prediction performance,verifying the effectiveness and practicality of this method. 展开更多
关键词 Photovoltaic power output prediction spatial downscaling CNN-iTransformer-LSTM Rime optimization random forest regression
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