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陕西佳县枣林生态系统环境适应性及服务功能价值评估

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干旱区研究 2014年第3期31卷 416-423页

作者：张永勋刘某承闵庆文伦飞张灿强中国科学院地理科学与资源研究所北京100101 福建师范大学地理科学学院福建福州350007 农业部农村经济研究中心北京100810

以陕西佳县枣林复合农业生态系统为研究对象,从环境适应性角度,综合分析其对环境的适应特征,评估其服务功能的经济价值。结果表明:枣树的生理结构、生长周期和耐受性适应佳县的自然环境,并且枣树对自然环境具有改造作用;枣具有丰富的营... 详细信息

以陕西佳县枣林复合农业生态系统为研究对象,从环境适应性角度,综合分析其对环境的适应特征,评估其服务功能的经济价值。结果表明:枣树的生理结构、生长周期和耐受性适应佳县的自然环境,并且枣树对自然环境具有改造作用;枣具有丰富的营养成分和药用价值,市场需求旺盛,良性的枣林生态系统为人类带来利益,长期形成的有关枣的神话和习俗等枣文化对人类破坏古枣树具有约束作用。佳县枣林生态系统服务功能价值巨大,据测算其主要服务功能的总经济价值为1.72×109元·a-1,其中,提供物质产品和保持土壤是最主要的服务功能。枣林生态系统对佳县的自然和社会环境具有显著的适应性,这种适应性和服务功能价值共同推动了其延续和发展。

关键词：农业文化遗产枣树(Zizyphus jujuba) 环境适应性生态系统服务功能佳县陕西

Observation of topological charge transformations in acoustic vortex using passive periodic systems

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 140-147页

作者： Di-Chao Chen Xie liu Changqing Xu Da-Jian Wu Ying cheng Xiao-Jun liu School of Physics and Technology Nanjing Normal University Key Laboratory of Modern Acoustics School of Physics Nanjing University

Vortex transmutation utilizes a periodic system, which not only enables the alteration of the topological charge(TC) of unstable input vortices but also facilitates their transformation into stable structures. This approach is crucial for investigating the characteristics of vortices in various wave systems. Here, we achieve acoustic vortex TC transmutation by employing a welldesigned dual-structured plate external system(DPES). The interactions between the acoustic vortex and the finite-order discrete rotational symmetry lead to the transformation of its topological charge when complete rotational symmetry is broken to Nthorder discrete symmetry. Our results experimentally demonstrate the acoustic vortex TC transmutation based on passive artificial structures, enabling numerous applications in particle manipulation and information multiplexing as well as advancing our understanding and control over free-space acoustic vortices.

关键词： acoustic vortex topological charge transformation artificial structure

Identifying the dynamic behaviors in complete reconstruction of Co-based complex precatalysts during electrocatalytic oxygen evolution

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Journal of Energy Chemistry 2025年第1期100卷 226-233页

作者： Jingfang Zhang Danyang Wu Linke Cai Youluan Lu Fanpeng cheng Lijuan Shi Qun Yi Yao liu Yi Huang Key Laboratory of Green Chemical Engineering Process of Ministry of Education Engineering Research Center of Phosphorus Resources Development and Utilization of Ministry of Education Hubei Key Laboratory of Novel Reactor and Green Chemical Technology School of Chemical Engineering & Pharmacy Wuhan Institute of Technology Key Laboratory of Pesticide & Chemical Biology of Ministry of Education Engineering Research Center of Photoenergy Utilization for Pollution Control and Carbon Reduction of Ministry of Education College of Chemistry Central China Normal University College of Materials Science and Engineering Fuzhou University

Transition metal-based nanomaterials have emerged as promising electrocatalysts for oxygen evolution reaction（OER）. Considerable research efforts have shown that self-reconstruction occurs on these nanomaterials under operating conditions of OER process. However, most of them undergo incomplete reconstruction with limited thickness of reconstruction layer, leading to low component utilization and arduous exploration of real catalytic mechanism. Herein, we identify the dynamic behaviors in complete reconstruction of Co-based complexes during OER. The hollow phytic acid（PA） cross-linked CoFe-based complex nanoboxes with porous nanowalls are designed because of their good electrolyte penetration and mass transport ability, in favor of the fast and complete reconstruction. A series of experiment characterizations demonstrate that the reconstruction process includes the fast substitution of PA by OH-to form Co（Fe）(OH)xand subsequent potential-driven oxidation to Co（Fe）OOH. The obtained CoFeOOH delivers a low overpotential of 290 mV at a current density of 10 mA cm-2and a long-term *** experiment results together with theory calculations reveal that the Fe incorporation can result in the electron rearrangement of reconstructed CoFeOOH and optimization of their electronic structure,accounting for the enhanced OER activity. The work provides new insights into complete reconstruction of metal-based complexes during OER and offers guidelines for rational design of high-performance electrocatalysts.

关键词： Complete reconstruction Co-based complex Precatalysts Oxygen evolution reaction

Preparation of FeCoNi medium entropy alloy from Fe^(3+)-Co^(2+)-Ni^(2+)solution system

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 92-101页

作者： Zongyou cheng Qing Zhao Mengjie Tao Jijun Du Xingxi Huang chengjun liu Key Laboratory for Ecological Metallurgy of Multimetallic Mineral(Ministry of Education) Northeastern UniversityShenyang 110819China School of Metallurgy Northeastern UniversityShenyang 110819China Engineering Research Center of Frontier Technologies for Low-carbon Steelmaking(Ministry of Education) Shenyang 110819China

In recent years,medium entropy alloys have become a research hotspot due to their excellent physical and chemical *** controlling reasonable elemental composition and processing parameters,the medium entropy alloys can exhibit similar properties to high entropy alloys and have lower *** this paper,a FeCoNi medium entropy alloy precursor was prepared via sol-gel and coprecipitation methods,respectively,and FeCoNi medium entropy alloys were prepared by carbothermal and hydrogen *** phases and magnetic properties of FeCoNi medium entropy alloy were *** showed that FeCoNi medium entropy alloy was produced by carbothermal and hydrogen reduction at 1500℃.Some carbon was detected in the FeCoNi medium entropy alloy prepared by carbothermal *** alloy prepared by hydrogen reduction was uniform and showed a relatively high ***,the hydrogen reduction product exhibited better saturation magnetization and lower coercivity.

关键词： medium entropy alloy sol-gel co-precipitation carbothermal hydrogen reduction

Spatial transcriptomics combined with single-nucleus RNA sequencing reveals glial cell heterogeneity in the human spinal cord

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Neural Regeneration Research 2025年第11期20卷 3302-3316页

作者： Yali Chen Yiyong Wei Jin liu Tao Zhu cheng Zhou Donghang Zhang Department of Anesthesiology West China HospitalSichuan UniversityChengduSichuan ProvinceChina Laboratory of Anesthesia and Critical Care Medicine National-Local Joint Engineering Research Center of Translational Medicine of AnesthesiologyWest China HospitalSichuan UniversityChengduSichuan ProvinceChina Department of Anesthesiology Longgang District Maternity&Child Healthcare Hospital of Shenzhen City(Longgang Maternity and Child Institute of Shantou University Medical College)ShenzhenGuangdong ProvinceChina Department of Anesthesiology Affiliated Hospital of Zunyi Medical UniversityZunyiGuizhou ProvinceChina

Glial cells play crucial roles in regulating physiological and pathological functions,including sensation,the response to infection and acute injury,and chronic neurodegenerative *** cells include astrocytes,microglia,and oligodendrocytes in the central nervous system,and satellite glial cells and Schwann cells in the peripheral nervous *** the greater understanding of glial cell types and functional heterogeneity achieved through single-cell and single-nucleus RNA sequencing in animal models,few studies have investigated the transcriptomic profiles of glial cells in the human spinal ***,we used high-throughput single-nucleus RNA sequencing and spatial transcriptomics to map the cellular and molecular heterogeneity of astrocytes,microglia,and oligodendrocytes in the human spinal *** explore the conservation and divergence across species,we compared these findings with those from *** the human spinal cord,astrocytes,microglia,and oligodendrocytes were each divided into six distinct transcriptomic *** the mouse spinal cord,astrocytes,microglia,and oligodendrocytes were divided into five,four,and five distinct transcriptomic subclusters,*** comparative results revealed substantial heterogeneity in all glial cell types between humans and ***,we detected sex differences in gene expression in human spinal cord glial ***,in all astrocyte subtypes,the levels of NEAT1 and CHI3L1 were higher in males than in females,whereas the levels of CST3 were lower in males than in *** all microglial subtypes,all differentially expressed genes were located on the sex *** addition to sex-specific gene differences,the levels of MT-ND4,MT2A,MT-ATP6,MT-CO3,MT-ND2,MT-ND3,and MT-CO_(2) in all spinal cord oligodendrocyte subtypes were higher in females than in ***,the present dataset extensively characterizes glial cell heterogeneity and offers a valuable resource for explo

关键词： astrocyte glial cell human microglia oligodendrocyte sex differentiation single-nucleus RNA sequencing spatial transcriptomics species variation spinal cord

基于管理分区的神农架国家公园生态监测指标体系构建

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长江流域资源与环境 2021年第6期30卷 1511-1520页

作者：姚帅臣闵庆文焦雯珺何思源刘某承张碧天刘显洋杨潇李文华中国人民大学环境学院北京100872 中国科学院地理科学与资源研究所北京100101 中国科学院大学北京100049

国家公园管理目标的实现依赖于大量监测数据和信息的支持,然而国家公园不同管理分区往往具有不同的管理目标,因此对于监测数据具有不同的需求。为满足国家公园不同管理分区管理的差异性需求、提高生态监测指标体系的针对性和监测效率,... 详细信息

国家公园管理目标的实现依赖于大量监测数据和信息的支持,然而国家公园不同管理分区往往具有不同的管理目标,因此对于监测数据具有不同的需求。为满足国家公园不同管理分区管理的差异性需求、提高生态监测指标体系的针对性和监测效率,探讨了基于管理分区的国家公园生态监测指标体系构建的可行性,并以神农架国家公园为例,应用面向国家公园管理目标的生态监测指标体系构建方法,构建出两个管护小区的生态监测指标体系。研究结果表明神农架国家公园两个管护小区在监测内容和监测指标上都存在差异,反映出两个小区管理目标的差异。这在一定程度上说明基于管理分区的生态监测指标体系更具有针对性,能够满足不同管理分区的监测需求,可为我国国家公园不同管理分区生态监测指标体系的构建提供借鉴。

关键词：国家公园生态监测管理分区指标体系神农架国家公园

农业文化遗产地农户生计资本与生计策略关系研究——以宽城传统板栗栽培系统为例

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原生态民族文化学刊 2020年第5期12卷 101-109页

作者：洪传春刘某承张永勋东北大学秦皇岛分校管理学院河北秦皇岛066004 东北大学工商管理学院辽宁沈阳110004 中国科学院地理科学与资源研究所北京100101 中国农业科学院农业经济与发展研究所北京100081

农业文化遗产地拥有独特的自然与文化资源禀赋,这构成了当地农户生计资本的一部分,分析农业文化遗产地农户生计资本与生计策略的关系对于提高农户生计水平、保护和发展农业文化遗产均具有重要意义。论文以宽城传统板栗栽培系统为例,依... 详细信息

农业文化遗产地拥有独特的自然与文化资源禀赋,这构成了当地农户生计资本的一部分,分析农业文化遗产地农户生计资本与生计策略的关系对于提高农户生计水平、保护和发展农业文化遗产均具有重要意义。论文以宽城传统板栗栽培系统为例,依据实地调查数据,在评估农户生计资本值的基础上,构建了无序多分类Logistic回归模型。研究表明:(1)农户的文化资本指数相对最高,自然、物质与金融资本相对缺乏,不同类型农户间的生计资本禀赋差异明显;(2)自然、人力和文化资本是农户由非板栗农业型向板栗农业型转型的关键影响因子;物质与金融资本对农户由非板栗农业型向兼农型和非农型生计策略转型具有正向影响,且影响程度逐渐加大;(3)家用汽车拥有情况、家庭借贷水平和收入水平对农户由非板栗农业型向兼农型和非农型生计策略转化均具有正向影响,且影响程度逐渐加大。在上述分析基础上,提出了保护与发展的相关建议,包括:积极依据相关法律法规,制定相应的管理办法,加大政策宣传力度,促进土地流转;通过教育、培训和提高医疗保障水平提升人力资本;加大财政金融支持力度,将普惠金融真正惠及到偏远山区。

关键词：宽城传统板栗栽培系统中国重要农业文化遗产农户生计资本生计策略宽城满族自治县

C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 pathway as a therapeutic target and regulatory mechanism for spinal cord injury

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Neural Regeneration Research 2025年第8期20卷 2231-2244页

作者： Xiangzi Wang Xiaofei Niu Yingkai Wang Yang liu cheng Yang Xuyi Chen Zhongquan Qi School of Medicine Guangxi UniversityNanningGuangxi Zhuang Autonomous RegionChina Graduate School of Tianjin University of Traditional Chinese Medicine TianjinChina Characteristic Medical Center of People’s Armed Police Forces TianjinChina Fujian Maternity and Child Health Hospital FuzhouFujian ProvinceChina

Spinal cord injury involves non-reversible damage to the central nervous system that is characterized by limited regenerative capacity and secondary inflammatory *** expression of the C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 axis exhibits significant differences before and after *** studies have revealed that the C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 axis is closely associated with secondary inflammatory responses and the recruitment of immune cells following spinal cord injury,suggesting that this axis is a novel target and regulatory control point for *** review comprehensively examines the therapeutic strategies targeting the C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 axis,along with the regenerative and repair mechanisms linking the axis to spinal cord ***,we summarize the upstream and downstream inflammatory signaling pathways associated with spinal cord injury and the C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 *** review primarily elaborates on therapeutic strategies that target the C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 axis and the latest progress of research on antagonistic drugs,along with the approaches used to exploit new therapeutic targets within the C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 axis and the development of targeted ***,there are presently no clinical studies relating to spinal cord injury that are focusing on the C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 *** review aims to provide new ideas and therapeutic strategies for the future treatment of spinal cord injury.

关键词： apoptosis C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 pathway C-C motif chemokine receptor 2 antagonists chemokine ligand 2 chemokine receptor 2 inflammation macrophage microglia spinal cord injury therapeutic method

农业文化遗产视角下的黄河流域生态保护与高质量发展

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环境生态学 2020年第8期2卷 1-8页

作者：杨伦闵庆文刘某承饶滴滴中国科学院地理科学与资源研究所北京100101 中国科学院大学北京100049

作为我国农耕文明重要的发源地之一,黄河流域创造并传承了类型多样、价值突出的农业文化遗产,这些农业文化遗产维持了流域生态平衡,保育了生物多样性,发挥着重要的生态系统服务功能。通过全面阐述黄河上游、中游和下游地区的农业文化遗... 详细信息

作为我国农耕文明重要的发源地之一,黄河流域创造并传承了类型多样、价值突出的农业文化遗产,这些农业文化遗产维持了流域生态平衡,保育了生物多样性,发挥着重要的生态系统服务功能。通过全面阐述黄河上游、中游和下游地区的农业文化遗产保护现状,在此基础上,系统总结了一批具有典型代表性的农业文化遗产在缓解区域生态系统退化、改善水土流失状况、解决水资源供给矛盾等方面的突出价值,以期为黄河流域的生态保护与高质量发展提供科学依据。

关键词：农业文化遗产黄河流域生态保护可持续发展