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Relationships between Genetic Diversity of Vascular Plant Species and Climate Factors

Journal of Resources and Ecology 2018年第6期9卷 663-672页

作者： tan jingfang WAN Jizhong LUO Fangli YU Feihai School of Nature Conservation Beijing Forestry UniversityBeijing 100083China Zhejiang Provincial Key Laboratory of Plant Evolutionary Ecology and Conservation Taizhou UniversityTaizhouZhejiang 318000China

Genetic diversity is crucial for plants to respond to global climate change,and exploring relationships between genetic diversity and climatic factors may help predict how global climate change will shape the genetic diversity of plants in the *** far,however,the extent and magnitude of the impact of climatic factors on the genetic diversity of plants has not been *** collected data from 68published papers on two widely used measures of genetic diversity of populations (average expected heterozygosity (He)and average observed heterozygosity (Ho))and on localities of populations of 79vascular plants,and extracted data on 19 climatic factors from *** then explored the relationships between measures of genetic diversity and climatic factors using linear *** of plant populations was significantly correlated with climatic factors in 58.7%(44)of the 75 species that used He as a measure of genetic diversity,and Ho was correlated with climatic factors in 65.1% (41)of the 63 species that used this genetic diversity *** general,Mean Temperature of Wettest Quarter, Precipitation Seasonality,Precipitation of Driest Quarter and Temperature Seasonality played a vital role in shaping He,and Ho was mostly correlated with Precipitation of Warmest Quarter,Mean Temperature of Wettest Quarter, Precipitation of Driest Quarter and Precipitation of Driest ***,the proportion of the significant correlations between genetic diversity of populations and climatic factors was higher for woody than for herbaceous species, and different climatic factors played different roles in shaping genetic diversity of these two growth *** results suggest that climate may play an important role in shaping genetic diversity of plant populations,that climatic change in the future may alter genetic diversity of plants,and that genetic diversity of different plant forms may respond to climatic change differently.

关键词： average expected heterozygosity average observed heterozygosity climate change growth form genetic variation SSR

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蔡和森民生思想述论

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理论界 2020年第4期 21-28页

作者：谭景芳中南民族大学马克思主义学院

民生问题的解决直接关系到社会的和谐与稳定,蔡和森在分析了近代中国半殖民地半封建社会的国情后,明确强调要通过建立社会主义制度创设解决民生问题的制度前提,通过发展生产力为民生问题的解决奠定坚实的物质基础;同时,他还提出要大力... 详细信息

民生问题的解决直接关系到社会的和谐与稳定,蔡和森在分析了近代中国半殖民地半封建社会的国情后,明确强调要通过建立社会主义制度创设解决民生问题的制度前提,通过发展生产力为民生问题的解决奠定坚实的物质基础;同时,他还提出要大力组织以"涨工资、减工时、改善生存环境"为目的的工人运动、以"打土豪、分田地"为目的的农民运动等一系列具体举措,这对近代中国民生问题的解决意义重大。他的民生思想中科学的内容,是毛泽东思想的重要组成部分,对于决胜全面建成小康社会具有重要的指导意义。

关键词：蔡和森民生思想当代启示

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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

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基于林德斯泰特-庞加莱法的双节拍器耦合系统同步规律研究

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物理与工程 2023年第5期33卷 46-52页

作者：谭景芳王成会莫润阳陕西师范大学物理学与信息技术学院陕西西安710119

本文在双节拍器耦合系统动力学方程的基础上,利用Runge-Kutta(龙格-库塔)法对振动系统进行数值分析,通过摆杆摆角随时间演化的曲线图像,讨论影响系统同步性质的因素。利用L-P(林德斯泰特-庞加莱)法研究相同双节拍器耦合系统的系统参数... 详细信息

本文在双节拍器耦合系统动力学方程的基础上,利用Runge-Kutta(龙格-库塔)法对振动系统进行数值分析,通过摆杆摆角随时间演化的曲线图像,讨论影响系统同步性质的因素。利用L-P(林德斯泰特-庞加莱)法研究相同双节拍器耦合系统的系统参数对于摆杆摆动振幅和摆动频率的影响,得到无耦合双节拍器系统的近似解,结合数值分析比较系统参数对同步周期和振幅的影响;在理论分析得到的近似同步周期中设定同步系数q值,并通过拟合函数进行拟合,拟合后得到的同步周期与数值分析的周期基本一致。本文能为更好地理解耦合系统的同步性质提供参考,也能为学生进行双节拍器同步物理实验提供一些理论参考,增强学生理论联系实际的能力。

关键词：耦合同步振动系统频率响应

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自动控制升降旗系统

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现代电子技术 2007年第11期30卷 115-119页

作者：张超谭静芳高秀美赵健泰山学院山东泰安271000 泰安市岱岳区技工学校山东泰安271000

本系统以单片机89C52为核心,以键盘为输入系统,其中键盘系统为矩阵式按键系统。按键选定执行要测试的旗杆高度参数,按开始键执行升旗程序,并将旗帜高度和升旗所用时间显示在LCD液晶显示屏上。测试的参数有3个:h(旗子的高度),t(升旗所用... 详细信息

本系统以单片机89C52为核心,以键盘为输入系统,其中键盘系统为矩阵式按键系统。按键选定执行要测试的旗杆高度参数,按开始键执行升旗程序,并将旗帜高度和升旗所用时间显示在LCD液晶显示屏上。测试的参数有3个:h(旗子的高度),t(升旗所用时间)以及v(步进电机的转速),通过秒表和米尺的方式来实现时间长短、旗杆高度及速度3个参数的获取。要求旗杆高度为1.8m、升降旗时间均各为43s,显示高度与实际高度之间的误差不大于2cm。

关键词： 89C52 LCD液晶步进电机升降旗系统

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Modulating the electrode–electrolyte interface enables switchable selectivity in electrocatalytic furfural reduction

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Science China Chemistry 2024年第10期67卷 3193-3194页

作者： jingfang Zhang Yi Huang Engineering Research Center of Phosphorus Resources Development and Utilization of Ministry of Education School of Chemical Engineering&PharmacyWuhan Institute of TechnologyWuhan 430205China College of Chemistry Central China Normal UniversityWuhan 430079China

Furfural(FF),an important bio-based platform molecule,can be valorized to high-value-added chemicals(e.g.,furfuryl alcohol(FA)or 2-methylfuran(MF))through catalytic hydrogenation[1].The traditional thermocatalytic transformation of FF always requires high-temperature and highpressure conditions[2].Accordingly,electrocatalytic hydrogenation is emerging as a promising approach for the selective reduction of FF to FA or MF under environmentally friendly and benign conditions.

关键词： hydrogenation electrolyte selectivity

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Influence of CeO2 loading on structure and catalytic activity for NH3-SCR over TiO2-supported CeO2

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Journal of Rare Earths 2020年第8期38卷 883-890,I0002页

作者： Hongliang Zhang Long Ding Hongming Long Jiaxin Li Wei tan Jiawei Ji jingfang Sun Changjin tang Lin Dong School of Metallurgical Engineering Anhui University of TechnologyMa'anshan 243032China Key Laboratory of Metallurgical Emission Reduction&Resources Recycling(Anhui University of Technology) Ministry of EducationMa'anshan 243002China Analysis and Testing Central Facility Anhui University of TechnologyMa'anshan 243002China Jiangsu Key Laboratory of Vehicle Emissions Control School of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210093China

A series of supported CeO2/TiO2 catalysts were prepared to explore the influence of CeO2 loading on these catalysts for the selective catalytic reduction of NO3 by NH3(NH3-SCR).The catalysts were investigated in detail by means of XRD,Raman,H2-TPR,NH3-TPD,XPS,in situ DRIFTS,and NH3-SCR *** activity of the catalyst is closely related to the content of *** the loading of CeO2 is near the dispersion capacity(1.16 mmol Ce4+/100 m^2 TiO2),the catalytic activity is *** may be because that the dispersed CeO2 is the active species and the catalyst has appropriate redox property,along with the larger amounts of surface Ce content and surface adsorbed oxygen ***,a possible reaction mechanism via the Langmuir-Hinshelwood(L-H)mechanism is tentatively proposed to further understand the NH3-SCR reaction.

关键词： CeO2 Selective catalytic reduction Redox property Dispersion capacity Structure-activity relationship Rare earths

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Mobility Analysis of Altmann Overconstrained Linkages by Modified Grübler-Kutzbach Criterion

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Chinese Journal of Mechanical Engineering 2011年第4期24卷 638-646页

作者： LIU jingfang LI Yanwen HUANG Zhen College of Mechanical Engineering andApplied Electronics Technology Beijing University of Technology Beijing 100124 China Robotics Research Center Yanshan University Qinhuangdao 066004 China

Developing a general mobility method/formula is a hot topic lasting for more than 150 years in kinematics. It is necessary to apply any mobility method to puzzling overconstrained mechanisms for verification of its generality. Altmann linkages are such recognized puzzling mechanisms that their mobility analysis is of important significance. A necessary condition for judging a general mobility method is that the method can be fit for Altmann linkages. Firstly, this study classes Altmann linkages into 17 types in terms of the numbers and types of kinematic pairs, and then Altmann overconstrained linkages are further classified into 4 types. Secondly, the mobility of Altmann overconstrained linkages is systematically analyzed by the Modified Grübler-Kutzbach criterion based on screw theory, where passive freedoms are defined as limb passive freedoms and mechanism passive freedoms. In addition, the full-cycle mobility is judged, which overcomes the shortcoming of instantaneous property of screw theory. It is shown that Modified Grübler-Kutzbach criterion not only obtains the correct numerical mobility, but also gives the mobility character by resolving reciprocal screws for the constraint system. This study lays the foundation of verification for the generality of Modified Grübler-Kutzbach criterion. Besides, Altmann overconstrained linkages almost comprise all kinds of modern parallel mechanisms and some classical mechanisms, which provides an important reference for mechanism mobility calculation.

关键词： mobility analysis overconstrained linkage screw theory

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RNA Imaging in Live Cells

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Chinese Journal of Chemistry 2023年第19期41卷 2531-2535页

作者： jingfang Zhao Limin Xiang College of Chemistry and Molecular Sciences&TaiKang Center for Life and Medical Sciences Wuhan UniversityWuhanHubei430072 China

Traditional molecular biology tools have elucidated the identities and functions of RNA molecules,which are essential to the understanding of gene transcription and protein *** this research field would further require the direct visualization of RNA dynamics such as the DNA-RNA interactions and RNA-protein *** this goal,the rise of RNA imaging tools over the past 15 years has reformed how we looked at these *** this Emerging Topic,we first highlighted recent advances on three main RNA imaging tools based on the species of interacting molecules:RNA-RNA pairing,RNA-protein binding,and small molecule-RNA *** introduced the advantages of these tools from a technical viewpoint,including binding affinity,fluorescent turn-on ratio,stability,and impacts on targeted ***,we discussed new rising opportunities and future directions,echoing the state-of-the-art imaging tools in the fields of fluorescent proteins and small fluorescent ***,we believe this emerging field will bring new insights on how we study RNA biology in living systems.

关键词： Fluorescent imaging RNA imaging Fluorogenic RNA RNA Fluorescent probes RNA recognition

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Design and Analysis of a Novel Compliant Mechanism with RPR Degrees of Freedom

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Chinese Journal of Mechanical Engineering 2022年第5期35卷 262-274页

作者： Shuang Zhang jingfang Liu Huafeng Ding College of Mechanical Engineering and Applied Electronics Technology Beijing University of TechnologyBeijing 100124China Key Laboratory of Advanced Manufacturing Technology Beijing University of TechnologyBeijing 100124China School of Mechanical Engineering and Electronic Information China University of Geosciences(Wuhan)Wuhan 430074China

A novel compliant mechanism with RPR degrees of freedom(DOF)is proposed where R and P represent rotation and translation DOFs,*** proposed compliant mechanism is obtained from dimension synthesizing a 2-RPU-UPR rigid parallel mechanism with the method of optimization of motion/force transfer characteristic.R,P and U represent rotation,translation and universal pairs,***,inverse kinematics and Jacobian matrix are analyzed for the dimensional ***,output transmission indexes of branches in the parallel mechanism are *** synthesis is completed based on the normalized design *** optimization of flexure joints based on constrained energy is carried ***,the novel compliant mechanism is obtained by direct replacing *** model of the compliant mechanism including static stiffness and input stiffness is built based on the pseudo-rigid body modeling method and virtual work ***,FEA simulation by Ansys Workbench is carried out to verify DOF,effectiveness of the dimension synthesis,and compliant *** of motion/force transfer characteristic is first applied for the design of compliant mechanisms to suppress drift of rotation axis in the paper.

关键词： Compliant mechanism RPR degrees of freedom Motion/force transfer characteristic Mechanical model Optimization

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