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Is the Cape Stone Forest in Shantou City formed by wave erosion? A comparison of the pedestal rocks on the coasts and the mountains of Queshi in eastern Guangdong, China

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Journal of Mountain Science 2024年第5期21卷 1447-1463页

作者： CHEN Min WANG wei School of Geography South China Normal UniversityGuangzhou 510631China

Cape Stone Forest is a group of granite rock pillars(pedestal rocks) towering over Shilin Lake, on the southern shore of Shantou Bay in eastern Guangdong, China. The rock pillars were previously identified as sea stacks because they have marine notch-like concave sidewalls at their base, and more importantly, the lake is immediately adjacent to the bay, which is exposed to the open sea. However, rock pillars similar in shape and size can also be found at the top of Queshi Mountain, which is only about 300 meters northwest of the lake and about 85 meters above sea level. Therefore, the marine origin of Cape Stone Forest is seriously questioned. In this study, 3D imagery and drone technology were used to collect data in the investigations without direct manual measurements in the water or on the mountain. It shows that the concave sidewalls of the rock pillars in the lake and on the mountains occur at different heights and are exposed to different directions, while a natural sea stack on Mayu Island at the mouth of Shantou Bay has a horizontal notch parallel to the sea level, although the granite rock of the sea stack is the same as that of the lake and the mountains. The eastern side of the island, where the sea stack is located, is exposed to the open sea but blocks large waves for the rock pillars in the lake. Therefore, the origin of Cape Stone Forest cannot be explained by wave-based mechanisms. The only satisfactory explanation that takes into account all the field evidence is that the narrow rock pillars of the lake and mountain were formed by chemical weathering that penetrated closely the spaced joints of the granite rock, and the notch-like concave sidewalls were formed by more effective chemical weathering at the base of the pillars.

关键词： Pedestal rock Granite Closely spaced joints Wave erosion Chemical weathering

Global Stability to Steady Supersonic Rayleigh Flows in One-Dimensional Duct

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Chinese Annals of Mathematics,Series B 2024年第2期45卷 279-296页

作者： Fenglun wei Jianli LIU Department of Mathematics Shanghai University Newtouch Center for Mathematics of Shanghai University

Heat exchange plays an important role in hydrodynamical systems,which is an interesting topic in theory and *** this paper,the authors consider the global stability of steady supersonic Rayleigh flows for the one-dimensional compressible Euler equations with heat exchange,under the small perturbations of initial and boundary conditions in a finite rectilinear duct.

关键词： Compressible Euler equations Heat exchange Supersonic Rayleigh fow Steady solution Classical solution

Two Applications of the ■■-Hodge Theory

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Chinese Annals of Mathematics,Series B 2024年第1期45卷 137-150页

作者： Dingchang wei Shengmao ZHU Center of Mathematical Sciences Zhejiang UniversityHangzhou 310027China Department of Mathematics Zhejiang Normal UniversityJinhua 321004ZhejiangChina

Using Hodge theory and Banach fixed point theorem,Liu and Zhu developed a global method to deal with various problems in deformation *** this note,the authors generalize Liu-Zhu's method to treat two deformation problems for non-Kahler *** apply the ■■-Hodge theory to construct a deformation formula for(p,q)-forms of compact complex manifold under deformations,which can be used to study the Hodge number of complex manifold under *** the second part of this note,by using the ■■-Hodge theory,they provide a simple proof of the unobstructed deformation theorem for the non-Kahler Calabi-Yau ■■-manifolds.

关键词： Complex structures Deformations (p,q)-Forms Non-Kahler Calabi-Yaumanifolds

Nest decoration:Black feathers prevent Crested Mynas from nest usurpation

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Avian Research 2024年第2期15卷 292-297页

作者： Jinmei Liu wei Liang Ministry of Education Key Laboratory for Ecology of Tropical Islands Key Laboratory of Tropical Animal and Plant Ecology of Hainan ProvinceCollege of Life SciencesHainan Normal UniversityHaikou571158China

Nests are important structures for birds to raise their offspring and for *** birds incorporate feathers into the nest,since feathers were traditionally thought to serve the function of *** in recent years have considered that some birds place feathers in conspicuous locations in the nest for decoration to trigger a fear response in the *** this study,we investigated whether decorative feathers could deter nest usurpation by Crested Mynas(Acridotheres cristatellus)by manipulating nest box *** results revealed that Crested Mynas preferred black feathers to white feathers as decorations and occupied nest boxes decorated with black feathers significantly less than those decorated with white feathers,suggesting that black decorative feathers in the nest could be more effective in preventing nest usurpation by Crested Mynas and that white decorative feathers may have other *** black feathers in the nest are prominently placed at the edge of the nest to convey the message that“this nest is occupied”or“the owner of this nest has been preyed upon”to visitor Crested Mynas,thus effectively preventing them from usurping the nest at a later stage.

关键词： Extended phenotype Feathers Nest decoration Nest usurpation

Steady-state Voltage Security-constrained Optimal Frequency Control for Weak HVDC Sending-end AC Power Systems

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Journal of Modern Power Systems and Clean Energy 2024年第2期12卷 658-669页

作者： Qiangqiang Wang Liangzhong Yao Jian Xu Yuping Zheng wei Li wei Wang School of Electrical Engineering and Automation Wuhan UniversityWuhan 430072China Hubei Engineering and Technology Research Center for AC/DC Intelligent Distribution Network(Wuhan University) Wuhan 430072China State Key Laboratory of Smart Grid Protection and Control NARI Group Corporation(State Grid Electric Power Research Institute)Nanjing 211106China

Due to the fact that a high share of renewable energy sources(RESs)are connected to high-voltage direct current(HVDC)sending-end AC power systems,the voltage and frequency regulation capabilities of HVDC sending-end AC power systems have *** has resulted in potential system operating problems such as overvoltage and overfrequency,which occur simultaneously when block faults exist in the HVDC *** this study,a steady-state voltage security-constrained optimal frequency control method for weak HVDC sending-end AC power systems is *** integrated virtual inertia control of RESs is employed for system frequency *** dynamic reactive power compensation devices are utilized to control the voltage of all nodes meet voltage security ***,an optimization model that simultaneously considers the frequency and steady-state voltage security constraints for weak HVDC sending-end AC power systems is *** optimal control scheme with the minimum total cost of generation tripping and additional dynamic reactive power compensation required is obtained through the optimization *** are conducted on a modified IEEE 9-bus test system and practical Qing-Yu line commutated converter based HVDC(LCC-HVDC)sending-end AC power system to verify the effectiveness of the proposed method.

关键词： Renewable energy source(RES) high-voltage direct current(HVDC) AC power system optimal frequency control steady-state voltage security dynamic reactive power compensation

On the Specificity of Nanozymes: A Perspective

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Chinese Journal of Chemistry 2024年第13期42卷 1515-1522页

作者： Gen wei Shuje Liu Yung-Kang Peng Hui wei Department of Biomedical Engineering College of Engineering and Applied SciencesNanjing National Laboratory of MicrostructuresJiangsu Key Laboratory of Artificial Functional MaterialsNanjing UniversityNanjingJiangsu 21023China Department of Chemistry.City University of Hong Kong Hong Kong 999077Hong Kong SARChina State Key Laboratory of Analytical Chemistry for Life Science School of Chemistry and Chemical EngineeringChemistry and Biomedicine Innovation Center(ChemBIC)Nanjing UniversityNanjingJiangsu 210023China NMPA Key Laboratory for Biomedical Optics HangzhouZhejiang 310018China

We have compiled eight promising strategies for enhancing the specificity and selectivity of nanozymes,as depicted in the comprehensive summary *** exhibit intricate and sophisticated structures,including substrate channels and active sites,which can inform the design of *** of these structural features and the application of facet engineering/doping techniques can significantly enhance the catalytic specificity of ***,the use of Molecularly Imprinted Polymers(MiPs)to coat nanozymes represents an effective approach to impart substrate ***,several straightforward stopgap strategies have been devised to improve nanozyme specificity for analytical applications,such as the integration of biorecognition elements and nanozyme sensor arrays through surface modification.

关键词： Nanozymes Enzymes Catalytic activity Specificity Perspective

Superconducting,Topological,and Transport Properties of Kagome Metals CsTi_(3)Bi_(5)and RbTi_(3)Bi_(5)

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Research 2024年第2期2023卷 753-762页

作者： Xin-wei Yi Zheng-wei Liao Jing-Yang You Bo Gu Gang Su School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China Department of Physics Faculty of ScienceNational University of Singapore117551Singapore Kavli Institute for Theoretical Sciences and CAS Center for Excellence in Topological Quantum ComputationUniversity of Chinese Academy of SciencesBeijing 100190China

The recently discovered ATi_(3)Bi_(5)(A=Cs,Rb)exhibit intriguing quantum phenomena including superconductivity,electronic nematicity,and abundant topological ***_(3)Bi_(5)present promising platforms for studying kagome superconductivity,band topology,and charge orders in parallel with *** this work,we comprehensively analyze various properties of ATi_(3)Bi_(5)covering superconductivity under pressure and doping,band topology under pressure,thermal conductivity,heat capacity,electrical resistance,and spin Hall conductivity(SHC)using first-principles *** superconducting transition temperature(Tc)of CsTi_(3)Bi_(5)and RbTi_(3)Bi_(5)at ambient pressure are about 1.85 and 1.92 *** subject to pressure,Tc of CsTi_(3)Bi_(5)exhibits a special valley and dome shape,which arises from quasi-two-dimensional compression to three-dimensional isotropic compression within the context of an overall decreasing ***,Tc of RbTi_(3)Bi_(5)can be effectively enhanced up to 3.09 K by tuning the kagome van Hove singularities(VHSs)and flat band through *** can also induce abundant topological surface states at the Fermi energy(EF)and tune VHSs across ***,our transport calculations are in excellent agreement with recent experiments,confirming the absence of charge density ***,SHC of CsTi_(3)Bi_(5)can reach up to 226h·(e·Ω·cm)^(-1)at *** work provides a timely and detailed analysis of the rich physical properties for ATi_(3)Bi_(5),offering valuable insights for further experimental verifications and investigations in this field.

关键词： doping superconductivity conductivity

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企业研究开发费用加计扣除税收政策研究

国际税收 2014年第11期 8-14页

作者：魏志梅国家税务总局税收科学研究所北京100038

建设创新型国家是我国一项长期国策。我国研发费加计扣除税收优惠政策在鼓励企业加大研发投入、促进科技进步等方面发挥了重要的作用。但随着经济的发展和科技的进步,该政策从适用的范围、认定的标准到优惠方式等都需要进一步改进。本... 详细信息

建设创新型国家是我国一项长期国策。我国研发费加计扣除税收优惠政策在鼓励企业加大研发投入、促进科技进步等方面发挥了重要的作用。但随着经济的发展和科技的进步,该政策从适用的范围、认定的标准到优惠方式等都需要进一步改进。本文全面总结了现行研发费加计扣除税收政策的积极效应和存在的主要问题,介绍了国际相关政策和管理经验,提出了优化我国研发费加计扣除税收政策的具体思路。

关键词：研发费加计扣除税收政策

The new challenges for the development of NH_(3)-SCR catalysts under new situation of energy transition in power generation industry

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Chinese Chemical Letters 2024年第6期35卷 95-103页

作者： Feibin wei Yongfang Rao Yu Huang wei Wang Hui Mei Science and Technology on Thermostructural Composite Materials Laboratory School of Materials Science and EngineeringNorthwestern Polytechnical UniversityXi’an 710072China Key Laboratory of Aerosol Chemistry and Physics State Key Laboratory of Loess and Quaternary Geology(SKLLQG)Institute of Earth EnvironmentChinese Academy of SciencesXi’an 710061China Center of Excellence in Quaternary Science and Global Change Chinese Academy of SciencesXi’an 710061China University of Chinese Academy of Sciences Beijing 100049China Department of Environmental Science and Engineering Xi’an Jiaotong UniversityXi’an 710049China

NH_(3)-SCR was one of the most promising de NO_x technologies and it has been widely applied in industrial NO_x ***,with the further development of energy transformation in power generation sector,the development of NH_(3)-SCR catalysts is facing some new *** is becoming an urgent problem to solve low catalytic activity and stability of NH_(3)-SCR catalysts at the working condition of ultra-low temperature(≤200℃)and high concentrations of H_(2)O+SO_(2) due to the gradual deployment of new energy power ***,the traditional coal-fired power plants would need flexible operation with the increasing share of renewable energy *** NH_(3)-SCR catalysts which were applied in coal-fired power industry would be requested to work in a wide temperature window from 200℃ to 500℃ in the near ***,in this review,we summarized the progress of NH_(3)-SCR catalysts in solving these different industrial problems in recent *** the research directions which were deserved to be focused on the development of NH_(3)-SCR catalysts for the energy transition of power generation sector are proposed.

关键词： NH_(3)-SCR NOx reduction Power generation Ultra-low temperature Wide temperature windows