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Atmospheric nitrogen deposition affects forest plant and soil system carbon:nitrogen:phosphorus stoichiometric flexibility:A meta-analysis

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Forest Ecosystems 2024年第3期11卷 307-317页

作者： Xiyan Jiang Xiaojing Wang Yaqi Qiao Yi cao Yan Jiao An Yang Mengzhou Liu Lei Ma Mengya Song Shenglei fu Key Laboratory of Geospatial Technology for the Middle and Lower Yellow River Regions College of Geography and Environmental ScienceHenan UniversityKaifeng475004China Henan Key Laboratory of Integrated Air Pollution Control and Ecological Security College of Geography and Environmental ScienceHenan UniversityKaifeng475004China Henan Dabieshan National Field Observation and Research Station of Forest Ecosystem Henan UniversityZhengzhou450046China

Background:Nitrogen(N)deposition affects forest stoichiometric flexibility through changing soil nutrient availability to influence plant ***,the effect of N deposition on the flexibility of carbon(C),N,and phosphorus(P)in forest plant-soil-microbe systems remains ***:We conducted a meta-analysis based on 751 pairs of observations to evaluate the responses of plant,soil and microbial biomass C,N and P nutrients and stoichiometry to N addition in different N intensity(050,50–100,>100 kg·ha^(-1)·year^(-1)of N),duration(0–5,>5 year),method(understory,canopy),and matter(ammonium N,nitrate N,organic N,mixed N).Results:N addition significantly increased plant N:P(leaf:14.98%,root:13.29%),plant C:P(leaf:6.8%,root:25.44%),soil N:P(13.94%),soil C:P(10.86%),microbial biomass N:P(23.58%),microbial biomass C:P(12.62%),but reduced plant C:N(leaf:6.49%,root:9.02%).furthermore,plant C:N:P stoichiometry changed significantly under short-term N inputs,while soil and microorganisms changed drastically under high N *** N addition primarily affected plant C:N:P stoichiometry through altering plant N content,while understory N inputs altered more by influencing soil C and P *** N significantly influenced plant and soil C:N and C:P,while ammonia N changed plant N:*** C:P and soil C:N were strongly correlated with mean annual precipitation(MAT),and the C:N:P stoichiometric flexibility in soil and plant under N addition connected with soil ***,N addition decoupled the correlations between soil microorganisms and the ***:N addition significantly increased the C:P and N:P in soil,plant,and microbial biomass,reducing plant C:N,and aggravated forest P ***,these impacts were contingent on climate types,soil layers,and N input *** findings enhance our comprehension of the plant-soil system nutrient cycling mechanisms in forest ecosystems and plant strategy responses to N deposition.

关键词： C:N:P stoichiometry Meta-analysis Forest ecosystem Nitrogen addition form Nutrient cycles

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Feasibility study of the photonuclear reaction cross section of medical radioisotopes using a laser Compton scattering gamma source

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Nuclear Science and Techniques 2024年第9期35卷 168-177页

作者： Yu-Ning Gu Wei-Juan Zhao Xi-guang cao Yu-Xuan Yang Ting-Kai Ma Zheng-Li Liao Fei-Long Xu Yu-Gang Ma School of Physics and Microeletronics Zhengzhou UniversityZhengzhou 450001China Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai 201210China Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China School of Nuclear Science and Technology University of South ChinaHengyang 421001China Key Laboratory of Nuclear Physics and Ion-beam Application(MOE) Institute of Modern PhysicsFudan UniversityShanghai 200433China Shanghai Research Center for Theoretical Nuclear Physics NSFC and Fudan UniversityShanghai 200438China

In recent years,the gap between the supply and demand of medical radioisotopes has increased,necessitating new methods for producing medical *** reactions based on gamma sources have unique advantages in terms of producing high specific activity and innovative medical ***,the lack of experimental data on reaction cross sections for photonuclear reactions of medical radioisotopes of interest has severely limited the development and production of photonuclear transmutation medical *** this study,the entire process of the generation,decay,and measurement of medical radioisotopes was simulated using online gamma activation and offline gamma measurements combined with a shielding gamma-ray *** on a quasi-monochromatic gamma beam from the Shanghai Laser Electron Gamma Source(SLEGS),the feasibility of this measurement of production cross section for surveyed medi-cal radioisotopes was simulated,and specific solutions for measuring medical radioisotopes with ultra-low production cross sections were *** feasibility of this method for high-precision measurements of the reaction cross section of medical radioisotopes was demonstrated.

关键词： Medical radioisotope Photonuclear reaction GEANT4 Shanghai Laser Electron Gamma Source(SLEGS) Low-background gamma-ray spectrometer

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Rotating tank experiments for the study of geophysical fluid dynamics

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Journal of Oceanology and Limnology 2024年第5期42卷 1385-1398页

作者： Changming DONG Xiaojie LU Yuli LIU Guoqing HAN Minghan fu Qian cao Yang ZHANG Xu CHEN Yeping YUAN International Geophysical Fluid Dynamics Laboratory Nanjing University of Information Science and TechnologyNanjing 210044China Department of Atmospheric and Oceanic Sciences University of CaliforniaLos Angeles CA 90095USA State Key Laboratory of Satellite Ocean Environment Dynamics Second Institute of OceanographyMinistry of Natural ResourcesHangzhou 310012China Southern Marine Science and Engineering guangdong Laboratory(Zhuhai) Zhuhai 519000China Zhejiang Ocean University Zhoushan 316022China guangdong Ocean University Zhanjiang 524088China Ocean University of China Qingdao 266100China Zhejiang University Hangzhou 310058China

Geophysical fluid dynamics(GFD)is an interdisciplinary field that studies the large-scale motion of fluids in the natural *** a wide range of applications such as weather forecasts and climate prediction,GFD employs various research approaches including in-situ observations,satellite measurements,numerical simulations,theoretical analysis,artificial intelligence,and physical model experiments in *** these approaches,rotating tank experiments provide a valuable tool for simulating naturally-occurring fluid motions in *** proportional scaling and proper techniques,scientists can reproduce multi-scale physical processes of stratified fluids in the rotation system,which allows for the simulation of essential characteristics of fluid motions in the atmosphere and *** this review,rotating tanks of various scales in the world are introduced,as these tanks have been actively used to explore fundamental scientific questions in ocean and atmosphere *** illustrate the GFD experiments,three representative cases are presented to demonstrate the frontier achievements in the the GFD study by using rotating tank experiments:mesoscale eddies in the ocean,convection processes,and plume *** references for the experimental procedures are *** studies are encouraged to further explore the utilization of rotating tanks with improvements in experimental design and integration of other research *** is a promising direction of GFD to help enhance our understanding of the complex nature of fluid motions in the natural world and to address the challenges posed by global environmental changes.

关键词： laboratory experiment rotating tank geophysical fluid dynamics(GFD)

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大学教师与中学教师关于《基本不等式》的“同课异构”评析

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数学教育学报 2015年第6期24卷 40-43页

作者：张蜀青曹广福广州大学数学与信息科学学院广东广州510006 广州市执信中学广东广州510095

介绍和总结了大学教师与中学教师关于基本不等式教学内容的不同设计,比较其异同.无论大学教师还是中学教师都非常注重教学过程中的启发诱导,但是他们的启发方式却明显不同：大学教师注重知识的学科价值与思想内涵,强调思想性的渗透,中... 详细信息

介绍和总结了大学教师与中学教师关于基本不等式教学内容的不同设计,比较其异同.无论大学教师还是中学教师都非常注重教学过程中的启发诱导,但是他们的启发方式却明显不同：大学教师注重知识的学科价值与思想内涵,强调思想性的渗透,中学教师则注重授课细节,重视解题技巧与落实.通过对这种不同视角的“同课异构”,分析大学教师与中学教师不同的教育理念,进而反思中学数学原理课教学中应该注意的问题.

关键词：同课异构基本不等式教学理念教学方法

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The dynamic characteristics of saturated remolded loess under cyclic load

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Earthquake Research Advances 2024年第2期4卷 27-35页

作者： Yuting fu Yanbo cao Jiaxu Kong Jia Zheng Jiaqi Mu Jie Wang Jianqi Zhuang College of Geological Engineering and Geomatics Key Laboratory of Western China Mineral Resources and Geological EngineeringChang’an UniversityXi’an710054China

Due to the joint development characteristic and macropore structure of loess,it is easy to cause structure collapse under earthquake or artificial *** study on the loess disaster effect and its mechanism under earthquake action is insufficient due to its ***,to study the deformation and mechanical properties more accurately,the dynamic characteristics of saturated remolded loess under cyclic dynamic load were tested using a GDS dynamic triaxial instrument in this *** test results show that strain and pore water pressure increase gradually at different rates with the development of vibration,and there is an obvious inflection point in the time-history curve of *** the number of vibrations(N)exceeds this point,the strain increases rapidly,and pore water pressure tends to be *** the action of large amplitude and low-frequency dynamic load,the strain and pore water pressure increase rapidly with fewer vibrations and the deviator stress(q)decreases rapidly,while the sample achieves damage faster with the increase of *** the application of a dynamic load,the effective stress(p)gradually decreases and its rate of change slows ***,when the saturated remolded loess is subjected to a constant-amplitude dynamic load,the combination of large amplitude and low frequency leads to the failure of the sample in the shortest time.

关键词： Loess Pore water pressure Strain Frequency Amplitude Quake(vibration)

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具有线性分式符号的紧复合算子的范数

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四川大学学报（自然科学版） 2009年第2期46卷 271-276页

作者：赵国俊曹广福曹志平南京工程学院基础部南京211167 广州大学数学与信息科学学院广州510006 中国中央国家机关工作委员会北京100081

作者研究了Hardy空间H^2上符号为φ的紧复合算子C_φ的范数,其中φ为D上的线性分式自映射。且当φ满足某类限制条件时,得到了关于‖C_φ‖的一个方程,利用此方程,可以求出‖C_φ‖的值。对于其它情形,作者给出了计算‖C_φ‖的一个等价... 详细信息

作者研究了Hardy空间H^2上符号为φ的紧复合算子C_φ的范数,其中φ为D上的线性分式自映射。且当φ满足某类限制条件时,得到了关于‖C_φ‖的一个方程,利用此方程,可以求出‖C_φ‖的值。对于其它情形,作者给出了计算‖C_φ‖的一个等价条件。

关键词：紧复合算子范数线性分式

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例论非数学专业学生同样需要数学思想

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数学教育学报 2009年第3期18卷 1-3页

作者：曹广福叶瑞芬广州大学数学与信息科学学院

大学非数学专业基础数学课程教学中存在着重计算、轻思想的现象,然而数学思想对大学生未来的成就将产生巨大影响,因此,非数学专业学生同样需要数学思想.以微积分课程为例,在函数、极限及连续性等问题的教学中,教师应强化数学思想的传授... 详细信息

大学非数学专业基础数学课程教学中存在着重计算、轻思想的现象,然而数学思想对大学生未来的成就将产生巨大影响,因此,非数学专业学生同样需要数学思想.以微积分课程为例,在函数、极限及连续性等问题的教学中,教师应强化数学思想的传授,培养学生的数学修养.

关键词：非数学专业数学思想数学理论微积分

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Controllable fabrication of FeCoS_(4) nanoparticles/S-doped bowl-shaped hollow carbon as efficient lithium storage anode

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Chinese Journal of Chemical Engineering 2024年第3期67卷 78-88页

作者： Ming Zhou Mengrong Wu Haiwei Yu Xiangjun Zheng Kuan Shen Xingmei Guo Yuanjun Liu fu cao Hongxing Gu Qinghong Kong Junhao Zhang School of Environmental and Chemical Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China Jiangsu Hengshen Co. LtdZhenjiang 212314China School of the Environment and Safety Engineering Jiangsu UniversityZhenjiang 212013China

To address the low conductivity and easy agglomeration of transition metal sulfide nanoparticles,FeCoS_(4) nanoparticles embedded in S-doped hollow carbon(FeCoS_(4)@S-HC)composites were successfully fabricated through a combination of hydrothermal processes and sulfidation *** unique bowlshaped FeCoS_(4)/S-HC composites exhibit excellent structural stability with a high specific surface area of 303.7 m^(2)·g^(-1) and a pore volume of 0.93 cm^(3)·g^(-1).When applied as anode material for lithium-ion batteries,the FeCoS_(4)@S-HC anode exhibits efficient lithium storage with high reversible specific capacity(970.2 mA·h·g^(-1) at 100 mA·g^(-1))and enhanced cycling stability(574 mA·h·g^(-1) at 0.2 A·g^(-1) after 350 cycles,a capacity retention of 84%).The excellent lithium storage is attributed to the fact that the bimetallic FeCoS_(4) nanoparticles with abundant active sites can accelerate the electrochemical reaction kinetics,and the bowl-shaped S-HC structure can provide a stable mechanical structure to suppress volume expansion.

关键词： Bimetallic sulfides Bowl-shaped hollow carbon S doping Buffering volume expand Lithium-ion batteries

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论数学课堂教学与评价的核心要素——以高中导数概念课为例

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数学教育学报 2016年第4期25卷 17-20页

作者：曹广福张蜀青广州大学数学与信息科学学院

评价数学课堂教学的核心要素是：是否挖掘出促使概念或原理产生的实质性问题;是否创设了真实且具有重要价值的问题情境;是否具有对问题的科学思考与辨析;逻辑是否严密;计算是否准确;学生是否能理解并熟练运用概念与原理.

关键词：问题核心要素导数概念课反思

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A Review on Engineering Transition Metal Compound Catalysts to Accelerate the Redox Kinetics of Sulfur Cathodes for Lithium–Sulfur Batteries

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Nano-Micro Letters 2024年第5期16卷 300-332页

作者： Liping Chen Guiqiang cao Yong Li Guannan Zu Ruixian Duan Yang Bai Kaiyu Xue Yonghong fu Yunhua Xu Juan Wang Xifei Li Shaanxi Key Laboratory of Nanomaterials and Nanotechnology Xi’an University of Architecture and TechnologyXi’an 710055People’s Republic of China Institute of Advanced Electrochemical Energy and School of Materials Science and Engineering Xi’an University of TechnologyXi’an 710048People’s Republic of China Yulin University Yulin 719000People’s Republic of China School of Materials Science and Engineering Fuzhou UniversityFuzhou 350108People’s Republic of China

Engineering transition metal compounds(TMCs)catalysts with excellent adsorption-catalytic ability has been one of the most effec-tive strategies to accelerate the redox kinetics of sulfur ***,this review focuses on engineering TMCs catalysts by cation doping/anion doping/dual doping,bimetallic/bi-anionic TMCs,and TMCs-based heterostructure *** is obvious that introducing cations/anions to TMCs or constructing heterostructure can boost adsorption-catalytic capacity by regulating the electronic structure including energy band,d/p-band center,electron filling,and valence ***,the elec-tronic structure of doped/dual-ionic TMCs are adjusted by inducing ions with different electronegativity,electron filling,and ion radius,resulting in electron redistribution,bonds reconstruction,induced vacancies due to the electronic interaction and changed crystal structure such as lat-tice spacing and lattice *** from the aforementioned two strategies,heterostructures are constructed by two types of TMCs with different Fermi energy levels,which causes built-in electric field and electrons transfer through the interface,and induces electron redistribution and arranged local atoms to regulate the electronic ***,the lacking studies of the three strategies to comprehensively regulate electronic structure for improving catalytic performance are pointed *** is believed that this review can guide the design of advanced TMCs catalysts for boosting redox of lithium sulfur batteries.

关键词： Lithium–sulfur battery Redox kinetic Transition metal compounds catalyst Multiple metals/anions

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