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Gradient maturation experiment on hairs implies taphonomic changes in fossil hairs

Science China Earth Sciences 2025年第1期68卷 62-73页

作者： xin li Yibo ZHOU Tao ZHAO xingjian HE Yanhong PAN State Key Laboratory for Mineral Deposits Research Center for Critical Earth Material Cycling Centre for Research and Education on Biological Evolution and Environment and Frontiers Science School of Earth Sciences and Engineering Nanjing University Institute of Palaeontology Yunnan Key Laboratory of Earth System Science Yunnan Key Laboratory for PalaeobiologyYunnan University

Mammalian hair, as a key feature related to endothermy, physical protection, and camouflage, has a long geohistorical record that dates back even to the Mesozoic. However, the limited information on the taphonomy of hair hinders the understanding of its evolutionary significance in deep time. To address this, we conducted taphonomic experiments to simulate the transformation process of black hair. The changes in the morphological structure, microscopic characteristics, and chemical composition of hair during the simulated fossilization process were documented by scanning electron microscopy, Fourier transform infrared(FTIR) spectroscopy, and Raman spectroscopy. Our results revealed that damage to the morphology of hair began at a mild temperature(150–175°C), and hair transformed into a fluid-like mass at a relatively high temperature(200°C). In addition, the morphological structure of melanosomes had relatively greater preservation potential than keratins did, and the microscopic features of melanosomes were persistently stable. The Raman and FTIR spectra indicated that the characteristic melanin and keratin peaks changed as the temperature increased. Although the chemical signals were not lost completely, the variations in the characteristic amide bands in the FTIR spectra indicate that the keratins severely degraded at high temperatures(>200°C), whereas the characteristic melanin bands in the Raman spectra suggested that melanin signals were still recognizable, even at high temperatures(>200°C). These results were confirmed by principal component analysis(PCA) and principal component analysis linear discriminant analysis(PCA–LDA). In addition, the Raman signals of all the samples in the simulated experiments were distinguished from the signals of common geological carbonaceous materials(humic acid), which suggested that Raman spectroscopy can be used to detect melanin in fossils.

关键词： Mammalian hair Melanin Keratin Fossilization Experimental taphonomy

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IoT Empowered Early Warning of Transmission line Galloping Based on Integrated Optical Fiber Sensing and Weather Forecast Time Series Data

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Computers, Materials & Continua 2025年第1期82卷 1171-1192页

作者： Zhe li yun liang Jinyu Wang Yang Gao State Grid Henan Electric Power Company Electric Power Scientific Research Institute State Grid Henan Electric Power CompanyZhengzhou450052China

Iced transmission line galloping poses a significant threat to the safety and reliability of power systems,leading directly to line tripping,disconnections,and power *** early warning methods of iced transmission line galloping suffer from issues such as reliance on a single data source,neglect of irregular time series,and lack of attention-based closed-loop feedback,resulting in high rates of missed and false *** address these challenges,we propose an Internet of Things(IoT)empowered early warning method of transmission line galloping that integrates time series data from optical fiber sensing and weather ***,the method applies a primary adaptive weighted fusion to the IoT empowered optical fiber real-time sensing data and weather forecast data,followed by a secondary fusion based on a Back Propagation(BP)neural network,and uses the K-medoids algorithm for clustering the fused ***,an adaptive irregular time series perception adjustment module is introduced into the traditional Gated Recurrent Unit(GRU)network,and closed-loop feedback based on attentionmechanism is employed to update network parameters through gradient feedback of the loss function,enabling closed-loop training and time series data prediction of the GRU network ***,considering various types of prediction data and the duration of icing,an iced transmission line galloping risk coefficient is established,and warnings are categorized based on this ***,using an IoT-driven realistic dataset of iced transmission line galloping,the effectiveness of the proposed method is validated through multi-dimensional simulation scenarios.

关键词： Optical fiber sensing multi-source data fusion early warning of galloping time series data IoT adaptive weighted learning irregular time series perception closed-loop attention mechanism

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High-throughput screening of CO_(2) cycloaddition MOF catalyst with an explainable machine learning model

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Green Energy & Environment 2025年第1期10卷 132-138页

作者： Xuefeng Bai Yi li Yabo Xie Qiancheng Chen xin Zhang Jian-Rong li Beijing Key Laboratory for Green Catalysis and Separation and Department of Chemical Engineering College of Materials Science&EngineeringBeijing University of TechnologyBeijing100124China

The high porosity and tunable chemical functionality of metal-organic frameworks(MOFs)make it a promising catalyst design ***-throughput screening of catalytic performance is feasible since the large MOF structure database is *** this study,we report a machine learning model for high-throughput screening of MOF catalysts for the CO_(2) cycloaddition *** descriptors for model training were judiciously chosen according to the reaction mechanism,which leads to high accuracy up to 97%for the 75%quantile of the training set as the classification *** feature contribution was further evaluated with SHAP and PDP analysis to provide a certain physical understanding.12,415 hypothetical MOF structures and 100 reported MOFs were evaluated under 100℃ and 1 bar within one day using the model,and 239 potentially efficient catalysts were *** them,MOF-76(Y)achieved the top performance experimentally among reported MOFs,in good agreement with the prediction.

关键词： Metal-organic frameworks High-throughput screening Machine learning Explainable model CO_(2)cycloaddition

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重嵌:乡贤治理形成的社会网络机制分析

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华中科技大学学报（社会科学版） 2023年第2期37卷 130-140页

作者：李云新程颖中南财经政法大学公共管理学院华中科技大学公共管理学院

作为传统自治主体,乡贤在全面推进乡村振兴、构建基层治理新格局中展现出新的时代价值。乡贤治理对提升乡村治理效能至关重要。本研究通过对鄂北L湾乡贤治理个案的追踪调研,基于社会网络理论构建“脱嵌—再建—重嵌”时序性分析框架,对... 详细信息

作为传统自治主体,乡贤在全面推进乡村振兴、构建基层治理新格局中展现出新的时代价值。乡贤治理对提升乡村治理效能至关重要。本研究通过对鄂北L湾乡贤治理个案的追踪调研,基于社会网络理论构建“脱嵌—再建—重嵌”时序性分析框架,对乡贤治理形成机制进行分析。研究表明,L湾乡贤治理经历了外出务工经商群体脱离乡土社会网络、乡土网络在城市中再建、乡贤返场重嵌乡土社会网络的过程,最终形成集中、公认、有力的兼具内生性和嵌入性的治理权威。依托乡土关系在城市中再建的外出务工经商群体网络,以情感符号重嵌乡村文化网络,以资源反哺重嵌并激活乡村经济网络,以乡贤权威重嵌乡村治理网络,推动乡贤治理的形成。在城乡融合发展背景下,城乡间流动的乡贤群体在城市找到合适位置的同时,如何进一步在推进乡村振兴中发挥作用,是实践中值得探索的重要方向和理论上亟待深入研究的重要课题。

关键词：乡村振兴乡村治理社会网络乡贤

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项目制运行过程中“示范”断裂现象及其解释

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华中科技大学学报（社会科学版） 2015年第5期29卷 62-70页

作者：李云新袁洋中南财经政法大学公共管理学院湖北武汉430073 中山大学政治与公共事务管理学院广东广州510006

中国试点工作呈现出"示范"断裂现象,即造点容易、推广难。"示范"断裂现象的发生,不仅因为选点不科学、操之过急或者综合配套试点不足、后济乏力,还在于中国宏观制度环境与中观制度安排下的微观政府行为异化。本文通过制度分析方法研究发... 详细信息

中国试点工作呈现出"示范"断裂现象,即造点容易、推广难。"示范"断裂现象的发生,不仅因为选点不科学、操之过急或者综合配套试点不足、后济乏力,还在于中国宏观制度环境与中观制度安排下的微观政府行为异化。本文通过制度分析方法研究发现"示范"断裂具有多重逻辑,宏观制度环境和中观制度安排提供了示范点建立的激励机制、示范失效的断裂机制以及路径依赖的强化机制,而示范断裂主要存在于资金链条断裂、科层运作断裂和集体行动断裂等多个环节中。国家治理、财政体制等集中式制度环境与统一目标、专款专用、配套资金、技术治理的项目制制度安排对地方政府"示范"工作的实施都产生了影响,且项目目标与科层目标间的张力是根本性矛盾。项目制制度安排为地方政府乐于"造点"、疲于"推广"提供了激励,而集中制环境对"示范"断裂予以路径强化,使得"示范"断裂现象常态化。

关键词：项目制示范国家治理政策试验

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Defect Engineering:Can it Mitigate Strong Coulomb Effect of Mg^(2+)in Cathode Materials for Rechargeable Magnesium Batteries?

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Nano-Micro Letters 2025年第1期17卷 135-159页

作者： Zhengqing Fan Ruimin li xin Zhang Wanyu Zhao Zhenghui Pan Xiaowei Yang School of Chemistry and Chemical Engineering Shanghai Jiao Tong UniversityShanghai 200240People’s Republic of China School of Chemistry and Chemical Engineering Taiyuan University of TechnologyTaiyuan 030024People’s Republic of China School of Materials Science and Engineering Tongji UniversityShanghai 201804People’s Republic of China

Rechargeable magnesium batteries(RMBs)have been considered a promising“post lithium-ion battery”system to meet the rapidly increasing demand of the emerging electric vehicle and grid energy storage ***,the sluggish diffusion kinetics of bivalent Mg^(2+)in the host material,related to the strong Coulomb effect between Mg^(2+)and host anion lattices,hinders their further development toward practical *** engineering,regarded as an effective strategy to break through the slow migration puzzle,has been validated in various cathode materials for *** this review,we first thoroughly understand the intrinsic mechanism of Mg^(2+)diffusion in cathode materials,from which the key factors affecting ion diffusion are further ***,the positive effects of purposely introduced defects,including vacancy and doping,and the corresponding strategies for introducing various defects are *** applications of defect engineering in cathode materials for RMBs with advanced electrochemical properties are also ***,the existing challenges and future perspectives of defect engineering in cathode materials for the overall high-performance RMBs are described.

关键词： Rechargeable magnesium battery Sluggish diffusion kinetic Defect engineering Cathode materials Ion migration

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后疫情时代国家对外应急语言能力建构刍议

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湘潭大学学报（哲学社会科学版） 2021年第6期45卷 174-179页

作者：仲文明李芸昕中南大学外国语学院湖南长沙410083

国家对外应急语言能力是国家语言能力的重要内容,也是国家应急管理体系和国家治理能力体系的组成部分。在回顾已有研究的基础上,提出国家对外应急语言能力的五个分项能力,并就后疫情时代系统构建国家对外应急能力,从加强顶层设计、加强... 详细信息

国家对外应急语言能力是国家语言能力的重要内容,也是国家应急管理体系和国家治理能力体系的组成部分。在回顾已有研究的基础上,提出国家对外应急语言能力的五个分项能力,并就后疫情时代系统构建国家对外应急能力,从加强顶层设计、加强对外应急语言基础设施建设、建构对外应急语言服务人才培养体系三个方面提出建议。

关键词：国家语言能力国家对外应急语言能力对外应急语言基础设施

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Wafer‑Scale Vertical 1D GaN Nanorods/2D MoS_(2)/PEDOT:PSS for Piezophototronic Effect‑Enhanced Self‑Powered Flexible Photodetectors

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Nano-Micro Letters 2025年第3期17卷 102-116页

作者： xin Tang Hongsheng Jiang Zhengliang lin Xuan Wang Wenliang Wang Guoqiang li State Key Laboratory of Luminescent Materials and Devices South China University of TechnologyGuangzhou 510640People’s Republic of China Department of Electronic Materials School of Materials Science and EngineeringSouth China University of TechnologyGuangzhou 510640People’s Republic of China

van der Waals(vdW)heterostructures constructed by lowdimensional(0D,1D,and 2D)materials are emerging as one of the most appealing systems in next-generation flexible ***,hand-stacked vdW-type photodetectors are not compatible with large-areaarray fabrication and show unimpressive performance in self-powered ***,vertical 1D GaN nanorods arrays(NRAs)/2D MoS_(2)/PEDOT:PSS in wafer scale have been proposed for self-powered flexible photodetectors arrays *** as-integrated device without external bias under weak UV illumination exhibits a competitive responsivity of 1.47 A W^(−1)and a high detectivity of 1.2×10^(11)Jones,as well as a fast response speed of 54/71μs,thanks to the strong light absorption of GaN NRAs and the efficient photogenerated carrier separation in type-II ***,the strain-tunable photodetection performances of device have been ***,the device at−0.78%strain and zero bias reveals a significantly enhanced photoresponse with a responsivity of 2.47 A W^(−1),a detectivity of 2.6×10^(11)Jones,and response times of 40/45μs,which are superior to the state-of-the-art self-powered flexible *** work presents a valuable avenue to prepare tunable vdWs heterostructures for self-powered flexible photodetection,which performs well in flexible sensors.

关键词： Vertical nanorod arrays van der Waals heterostructure Piezophototronic effect Self-powered photodetection Flexible sensors

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新农村建设中的“示范”:实践模式与运行效果

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西北农林科技大学学报（社会科学版） 2014年第6期14卷 8-14页

作者：李云新袁洋中南财经政法大学公共管理学院武汉430073

"示范"是新农村建设的一种重要机制,是政策过程、经济过程和社会过程的结合体。研究表明:在新农村建设中"示范"的实践模式分为政府主导型和社会自发型两大类;"示范"模式的运行效果不尽相同,产生了正反两方面的示范效应;示范内容属性、... 详细信息

"示范"是新农村建设的一种重要机制,是政策过程、经济过程和社会过程的结合体。研究表明:在新农村建设中"示范"的实践模式分为政府主导型和社会自发型两大类;"示范"模式的运行效果不尽相同,产生了正反两方面的示范效应;示范内容属性、社会系统性质、传播渠道、时间和空间等因素显著影响了新农村建设中"示范"的运行效果,应从实践模式的有效互补、增强示范经验与接受方的匹配度与兼容性、充分整合利用传播渠道增强扩散效果、把握时空维度上运行规律等方面促进"示范"的有效运行。

关键词：示范新农村建设实践模式示范效果

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资本下乡与乡村精英再造

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华南农业大学学报（社会科学版） 2018年第5期17卷 117-125页

作者：李云新阮皓雅中南财经政法大学公共管理学院湖北武汉430073

在工商资本大规模下乡背景下,回流人才及村庄内的部分精英农户抓住时机、响应机会并采取行动,在公司主义的包围中成为乡村场域中另一部分拥有相对话语权的群体,完成了乡村精英的重塑。乡村新精英的产生是政策驱动、资本推动、精英回流... 详细信息

在工商资本大规模下乡背景下,回流人才及村庄内的部分精英农户抓住时机、响应机会并采取行动,在公司主义的包围中成为乡村场域中另一部分拥有相对话语权的群体,完成了乡村精英的重塑。乡村新精英的产生是政策驱动、资本推动、精英回流的共同结果。新精英通过和资本同盟积极响应经济机会,与基层政府结成"权力—利益"共同体谋求政治嵌入,凭借熟人网络带动和俘获普通农户以强化社会关联。乡村精英再造具有双重效应,对乡村治理产生深远影响。新精英的兴起激发了乡村内源发展动力,有利于实现乡村振兴,但也由于资源分配的不平衡加剧了乡村阶层分化。

关键词：资本下乡乡村精英乡村振兴乡村治理城乡一体化

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