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The low-latitude sodium layer:comparative data from lidar observations at Hainan,China and São Paulo,Brazil

Earth and Planetary Physics 2025年第1期9卷 39-53页

作者： Fang Wu Jing Jiao guoTao Yang LiFang Du ZhengKuan Liu HaoRan Zheng JiXin guo ShaoHua Gong YaJun Zhu State Key Laboratory of Space Weather National Space Science CenterChinese Academy of SciencesBeijing 100190China Hainan National Field Science Observation and Research Observatory for Space Weather National Space Science CenterChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China China-Brazil Joint Laboratory for Space Weather NSSC/INPESão Josédos Campos 12227-010Brazil School of Physics and Electronics Engineering Hainan Normal UniversityHaikou 571158China

Physical and chemical processes observed in the mesosphere and thermosphere above the Earth’s low latitudes are complex and highly interrelated to activity in the low-latitude *** sodium detected by lidar can yield clues to dynamic and chemical processes in these spatial layers above the Earth’s *** paper is based on sodium layer data collected at two low-latitude stations,one in the northern hemisphere and one in the *** low-latitude sodium layer exhibits conspicuous seasonal variations in shape,density,and altitude;these variations are similar between Earth’s hemispheres:sodium layer density at both stations reaches its seasonal maximum in autumn and minimum in ***,maximal Na density over Brazil is greater than that over *** variations of Na density above the two low-latitude stations are also similar;at both,maxima are observed before *** variations of the Na layer over Brazil that differ from those observed in the northern hemisphere may be related to the South Atlantic Magnetic Anomaly(SAMA)or fountain *** suggest that low-latitude Na layer data may provide useful additional evidence that could significantly improve the low-latitude part of the WACCM-Na model.

关键词： metallic sodium layer seasonal variation nocturnal variation lidar

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Enhancing anion conductivity in a highly alkali-stable eta topologic Cu(Ⅰ) framework via strong electrostatic repulsion

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Science China Chemistry 2025年

作者： Xiaolu Wang Shaohui guo Chao Suo Fuqiang Zhang Junhao Wang Wenjing Wang Daqiang Yuan Linfeng Liang Xianming Zhang College of Chemistry Taiyuan University of Technology Institute of Crystalline Materials Shanxi University School of Chemistry and Materials Science Shanxi Normal University State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences

Metal-organic frameworks （MOFs） based on anion exchange membranes （AEMs） have garnered considerable interest,particularly for their potential to enhance ion conductivity by pre-introducing anions into *** approach is recognized as straightforward and effective for improving ion ***,developing high-performance AEMs is limited by the inherent instability and low resistance of *** study presents a novel 1,3,5-triazineμ3-bridged neutral Cu（I） framework,designated SXU-120 （where SXU represents Shanxi University）.This framework is synthesized using melamine,a widely available industrial product,as the starting material,achieving a high space-time yield exceeding 1.1 kg *** organic ligands and metal ions in SXU-120 are 3-connected,forming a rare eta topology with the point symbol 8～***-120 exhibits exceptional stability,even in a 10 M KOH solution,due to its high density of uncoordinated–NH2and carbonyl ***,the framework’s unique one-dimensional channels,characterized by their electronegativity,interact electrostatically with OH-ions,thereby accelerating OH-ion transfer along these ***,the OH-conductivity of this material reaches an impressive 0.49 S cm-1at 90°C under full humidity for 100 h,representing the highest OH-conductivity reported for MOF-based conductors to *** properties make SXU-120 a promising candidate for efficient AEM materials in next-generation industrial applications.

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Dietary carbohydrate intake and risk of type 2 diabetes:a 16-year prospective cohort study

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Science China Life Sciences 2025年

作者： Lu Gan Yi Yang Bin Zhao Kai Yu Kehua guo Fang Fang Zhiguang Zhou Demetrius Albanes Jiaqi Huang Key Laboratory of Diabetes Immunology Ministry of Education and Department of Metabolism and Endocrinology The Second Xiangya Hospital of Central South University CSU-Sinocare Research Center for Nutrition and Metabolic Health Xiangya School of Public Health Central South UniversityFurong Laboratory Division of Cancer Epidemiology and Genetics National Cancer Institute NIH Department of Health and Human Services School of Computer Science and Engineering Central South University Institute of Environmental Medicine Karolinska Institute National Clinical Research Center for Metabolic Diseases Key Laboratory of Diabetes Immunology Ministry of Education and Department of Metabolism and Endocrinology The Second Xiangya Hospital of Central South University

Despite considerable research underscoring the importance of carbohydrate intake in relation to the risk of type 2 diabetes(T2D), a comprehensive assessment of this relationship is currently lacking. We aimed to examine the associations of various types and food sources of dietary carbohydrate intake with the risk of T2D, to evaluate potential effect modification by other factors, including genetic susceptibility,and to explore the potential mediators for such associations. The present study included 161,872 participants of the UK Biobank who were free of prevalent cancer, cardiovascular disease, or diabetes, and had at least one validated 24-h dietary recall assessment. Multivariableadjusted age-stratified Cox proportional hazard regression models were applied to estimate hazard ratios(HRs) and 95% confidence intervals(CI) for the associations of various types and food sources of dietary carbohydrate intake with risk of T2D. During a median follow-up of13.6 years, 4,176 incident cases of T2D were identified. In the multivariable-adjusted models, a greater intake of fiber, carbohydrates from whole grains, and carbohydrates from non-starchy vegetables was significantly associated with a lower risk of T2D(highest vs. lowest quantile, HR [95% CI]=0.70 [0.62–0.79], 0.74 [0.67–0.82], and 0.83 [0.75–0.92], respectively, all P for trend <0.005). In contrast, a higher intake of starch and carbohydrate from starchy vegetables was associated with an increased risk of T2D(highest vs. lowest quantile, HR [95%CI]=1.31 [1.16–1.48] and 1.19 [1.09–1.31], respectively, both P for trend <0.005). Replacing one serving of refined grains or starchy vegetables with an equal amount of whole grains or non-starchy vegetables was associated with 4% to 10% lower risk of T2D(all P values <0.001).The observed associations were generally similar across population subgroups, including individuals with different genetic susceptibility to T2D. Mediation analyses of the inverse association between T

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Voxel event graph neural network for event-based human gait recognition

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Optoelectronics Letters 2025年

作者： MA Guangyuan GONG Xiaolin XU Jiangtao GAO Jiandong guo Zhaoxuan School of Microelectronics， Tianjin University

To improve the accuracy of event-based gait recognition， a method called voxel event graph neural network (VEGNN) is proposed. This method voxelizes the event stream and selects representative voxels as vertices of the graph. Then the edges are constructed based on spatio-temporal distance and temporal order constraints so that the event stream is constructed as a graph structure. Finally， a lightweight feature extraction network based on graph neural networks (GNNs) is used to efficiently capture spatio-temporal information and motion cues from the event graph. To evaluate our method， an event-based gait recognition dataset called Celex-Gait is created. Experimental results show that VEGNN achieves a gait recognition accuracy of 95.8% (best among all methods) and 93.9% (second best among all methods) on the Celex-Gait dataset and the DVS128-Gait-Day dataset， respectively. Furthermore， compared to the state-of-the-art methods， VEGNN reduces the number of model parameters by 30%. This indicates that VEGNN achieves higher recognition accuracy with lower model complexity.

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Extensions and Deformations of 3-Lie Algebras with Higher Derivations

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Journal of Mathematical Research with Applications 2025年第1期 20-32页

作者： Shuangjian guo School of Mathematics and Statistics Guizhou University of Finance and Economics

In this paper, we call a tuple consisting of 3-Lie algebra and a higher derivation on it a 3-LieHDer pair. We introduce a cohomology theory of 3-LieHDer pairs. Next, we interpret the second cohomology group as the space of all isomorphism classes of abelian extensions. Finally,we consider formal deformations of 3-LieHDer pairs that are governed by the cohomology with self-coefficient.

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Ni-catalyzed cross-electrophile alkyl-alkyl coupling reactions

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Science China Chemistry 2025年

作者： Li-Xu You Lan Tian Chun-Ling guo Shun-Xi Li Yu-Cheng Liu Yu-Long Li Wei Shu College of Chemistry and Environmental Engineering Key Laboratory of Green Catalysis of Higher Education Institutes of Sichuan Sichuan University of Science and Engineering Guangming Advanced Research Institute Shenzhen Grubbs Institute Department of Chemistry and Guangdong Provincial Key Laboratory of Catalysis Southern University of Science and Technology

Introducing saturated carbon-carbon bonds into organic molecules significantly increases the three-dimensional configuration,thus altering the physical and chemical properties as well as the functions of molecules. Transition-metal-catalyzed carboncarbon cross-couplings represent one of the most straightforward, efficient and modular alternatives to build saturation in a single step. However, the efficient construction of alkyl-alkyl bonds remains a formidable challenge due to the precise manipulation of multiple alkyl metallic intermediates as well as associated competitive side reactions and selectivity control. Over the past years, Ni-catalyzed cross-coupling under reductive conditions has gained more and more attention for alkyl-alkyl crosscoupling partially attributing to the low-valent state of metal centers under reducing conditions, which suppresses the competitive β-hydride elimination process, thus facilitating the formation of alkyl-alkyl bonds. In this review, the initiative and progress of Ni-catalyzed cross-electrophile alkyl-alkyl cross-coupling, including the efforts in racemic and enantioselective formation of alkyl-alkyl bonds, have been summarized and discussed. Moreover, the challenges and further opportunities in this area have also been discussed.

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旅游地魅力对旅游者忠诚影响的中介与调节作用

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海南大学学报（人文社会科学版） 2025年第1期43卷 236-246页

作者：郭安禧郭英之上海商学院酒店管理学院上海201400 复旦大学旅游学系上海200433

旅游地魅力是近些年被提出和关注的新话题,目前考察旅游地魅力如何影响旅游者忠诚的研究尚少。本研究基于理智人模型、心理连续体模型和期望不一致理论,以享乐幸福感、实现幸福感、地方依赖、地方认同为中介和旅游体验质量为调节,探讨... 详细信息

旅游地魅力是近些年被提出和关注的新话题,目前考察旅游地魅力如何影响旅游者忠诚的研究尚少。本研究基于理智人模型、心理连续体模型和期望不一致理论,以享乐幸福感、实现幸福感、地方依赖、地方认同为中介和旅游体验质量为调节,探讨旅游地魅力对旅游者忠诚影响的中介路径和边界条件。通过对旅游者问卷调查获得的444份有效问卷进行实证分析,结果显示:旅游地魅力对旅游者忠诚没有显著直接影响,享乐幸福感、地方依赖、地方认同在二者间起完全中介作用;旅游地魅力能提升享乐幸福感和实现幸福感,享乐幸福感会提升旅游者忠诚度,但实现幸福感不会提升旅游者忠诚度;旅游地魅力能增强地方依赖和地方认同,地方依赖和地方认同又能增强旅游者忠诚;旅游体验质量在旅游地魅力与实现幸福感、地方依赖、地方认同的作用关系中起正向调节作用。

关键词：旅游地魅力旅游者幸福感地方依恋旅游者忠诚旅游体验质量

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Efficient and Stable Photoassisted Lithium‑Ion Battery Enabled by Photocathode with Synergistically Boosted Carriers Dynamics

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Nano-Micro Letters 2025年第3期17卷 440-454页

作者： Zelin Ma Shiyao Wang Zhuangzhuang Ma Juan Li Luomeng Zhao Zhihuan Li Shiyuan Wang Yazhou Shuang Jiulong Wang Fang Wang Weiwei Xia Jie Jian Yibo He Junjie Wang Pengfei guo Hongqiang Wang State Key Laboratory of Solidification Processing Center for Nano Energy MaterialsSchool of Materials Science and EngineeringNorthwestern Polytechnical University and Shaanxi Joint Laboratory of Graphene(NPU)Xi’an 710072People’s Republic of China State Key Laboratory of Solidification Processing School of Materials Science and Engineering DepartmentNorthwestern Polytechnical UniversityXi’an 710072People’s Republic of China State Key Laboratory of Solidification Processing Center of Advanced Lubrication and Seal MaterialsSchool of Materials Science and EngineeringNorthwestern Polytechnical UniversityXi’an 710072People’s Republic of China Research and Development Institute of Northwestern Polytechnical University in Shenzhen Shenzhen 518063People’s Republic of China Key Laboratory of Applied Surface and Colloid Chemistry Shaanxi Key Laboratory for Advanced Energy DevicesShaanxi Engineering Lab for Advanced Energy TechnologySchool of Materials Science and EngineeringNational Ministry of EducationShaanxi Normal UniversityXi’an 710119People’s Republic of China

Efficient and stable photocathodes with versatility are of significance in photoassisted lithium-ion batteries(PLIBs),while there is always a request on fast carrier transport in electrochemical active *** work proposes a general approach of creating bulk heterojunction to boost the carrier mobility of photocathodes by simply laser assisted embedding of plasmonic *** employed in PLIBs,it was found effective for synchronously enhanced photocharge separation and transport in light charging ***,experimental photon spectroscopy,finite difference time domain method simulation and theoretical analyses demonstrate that the improved carrier dynamics are driven by the plasmonic-induced hot electron injection from metal to TiO_(2),as well as the enhanced conductivity in TiO2 matrix due to the formation of oxygen vacancies after Schottky *** from these merits,several benchmark values in performance of TiO2-based photocathode applied in PLIBs are set,including the capacity of 276 mAh g^(−1)at 0.2 A g^(−1)under illumination,photoconversion efficiency of 1.276%at 3 A g^(−1),less capacity and Columbic efficiency loss even through 200 *** results exemplify the potential of the bulk heterojunction strategy in developing highly efficient and stable photoassisted energy storage systems.

关键词： Photoassisted lithium-ion batteries Bulk heterojunction Carrier dynamics TiO2 nanofiber Plasmonic metal nanocrystals

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Deliberate design of MOF-based pre-catalyst rationalizing the structural reconstruction toward efficient oxygen evolution reaction

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Science China Chemistry 2025年

作者： Yunhui Chen Meng Tian Zhongqi Zhang Guangzhao Wang Yan guo Jing Wu Dawei Qi Zhenhua Yan Xiangyu Liu Xi Liu State Key Laboratory of High-efficiency Coal Utilization and Green Chemical Engineering College of Chemistry and Chemical EngineeringNingxia University Key Laboratory of Extraordinary Bond Engineering and Advanced Materials Technology of Chongqing School of Electronic Information Engineering Yangtze Normal University Frontiers Science Center for New Organic Matter Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education) State Key Laboratory of Advanced Chemical Power Sources College of Chemistry Nankai University School of Chemistry and Chemical Engineering In-situ Center for Physical Sciences Frontiers Science Center for Transformative Molecules Shanghai Jiao Tong University

Metal-organic frameworks （MOFs）,that have emerged as promising electrocatalysts in oxygen evolution reaction （OER）,usually undergo structural reconstruction to form metal hydroxides as active ***,it remains a great challenge to design and synthesize ideal MOF-based pre-catalysts for properly cognizing and utilizing the reconstruction process toward efficient OER ***,the well-defined MOF-808 is post-modified by 2-hydroxyphosphonoacetic acid （HPAA） to form a micro-adsorber that enables to capture of metal ions ***3+and Ni2+ions are synergistically anchored into the microadsorber,developing a Fe/Ni-containing pre-catalyst that can be dynamically electrooxidized to be an active and stable dual-site electrocatalyst denoted by R-MOF-HPAA@FeNi with abundant metal *** a result,R-MOF-HPAA@FeNi exhibits an excellent OER performance with a low overpotential of 272 mV and Tafel slope of 35.9 m V dec-1,as well as long-term stability over 300 h at 10 m A *** and theoretical calculations suggest the resulting catalyst mainly follows a lattice oxygen mechanism （LOM） of dual-metal-site mechanism （DMSM）.Owing to the chelating role of HPAA,the post-synthesized MOF-HPAA behaves as a trap to uniformly and firmly adhere Fe3+and Ni2+ions,leading to a functionalized MOF-based pre-catalyst which can be structurally evolved into atomic level-distributed OER electrocatalysts.

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Imidazolium-based ionic polymers for fast and efficient anion-exchange driven capture of Cr2O72-

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Science China Chemistry 2025年

作者： Yishou Wang Xiaonan Yuan Xingxing Gou Xiatian Song Xiaogang Wang Ling guo Yanfeng Liu Chengfang Qiao Chunsheng Zhou Yingfeng Han Shaanxi Key Laboratory of Comprehensive Utilization of Tailings Resources Shaanxi Engineering Research Center for Mineral Resources Clean & Efficient Conversion and New Materials College of Chemical Engineering and Modern Materials Shangluo University Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of the Ministry of Education Xi'an Key Laboratory of Functional Supramolecular Structure and Materials College of Chemistry and Materials Science Northwest University

The pervasive issue of chromium（VI） contamination,particularly in dichromate (Cr2O2-7),resulting from unchecked industrial growth and inadequate waste management,remains a pressing concern that demands immediate and dedicated ***,we present two novel imidazolium-based ionic polymers （ImIPs）.The ImIPs boast a highly cationic structure rich in bromide（Br-） ions and exhibit remarkable porosity,facilitating the easy exchange of these ions for chromate (Cr2O2-7) through anion *** unique combination leads to exceptional performance,including a high adsorption capacity （423 mg/g）,rapid adsorption rate (75 mg g-1min-1),and a broad operational pH range （2–12）.Moreover,our material demonstrates remarkable reusability,maintaining its efficacy even after 10 cycles without significant loss of *** mechanistic studies underscore the role of ion-exchange chemistry in effectively removing dichromate by the presented ImIPs,providing strong evidence for their suitability as a robust solution to address the ongoing challenges in water *** findings represent a crucial step in developing advanced materials for tackling chromium（VI） pollution.

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