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Flexible nest site selection of the endangered Oriental Storks(Ciconia boyciana):Trade-off from adaptive strategies

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Avian Research 2023年第2期14卷 242-249页

作者： Lei Cheng lizhi Zhou Chao Yu Zhenhua Wei Chunhua Li School of Resources and Environmental Engineering Anhui UniversityHefei230601China School of Biological Engineering Huainan Normal UniversityHuainan232038China Anhui Province Key Laboratory of Wetland Ecosystem Protection and Restoration(Anhui University) Hefei230601China Anhui Shengjin Lake Wetland Ecology National Long-term Scientific Research Base Dongzhi247230China College of life and Environment Science Huangshan UniversityHuangshan245021China

Nest site selection is a vital component of bird reproduction success,and an adaptive behavior conducted to decrease nest predation risk with avoiding external disturbances.Understanding patterns of nest site selection can provide insights into how species adapt to changes in their habitat and has important conservation implications.In this study,we used microhabitat variables and multi-scale data with a field survey of nest occurrence to determine nest site selection patterns and adaptive strategies of the breeding Oriental Storks(Ciconia boyciana)in different nest areas.Results demonstrate that the nest site microhabitat characteristics of the breeding Oriental Storks significantly differed among the three nesting areas,and nest height was higher in the middle and lower Yangtze River floodplain than in the Northeast China and Bohai Bay nest areas.The food resources and intensity of human disturbance had the greatest effects on the nest site selection of the breeding Oriental Storks.The intensity of human disturbance was positively correlated with the nest height of the breeding Oriental Storks in Bohai Bay and the middle and lower Yangtze River floodplain;however,nest height decreased with the abundance of food resources in the Northeast China nest area.Our findings indicate that the nest site selection patterns of Oriental Storks showed flexible adaptive strategies.In safer environments,nests were lower and closer to food resources,which allows parent storks to invest more in the nestlings.However,in areas where human activity was intense,nests were higher to ensure the safety of their offspring.Some measures that could be taken to improve the breeding habitat of Oriental Storks include increasing the percentage of wetland areas in nesting areas to enhance food resources availability and setting artificial nests at suitable heights in potential nesting grounds to encourage nesting.Finally,the establishment of soft barriers around the nesting areas could increase the safety of nests.

关键词： Adaptive strategies Breeding range expansion Habitat characteristics Nest site selection Oriental storks

Rapid decrease in Antarctic sea ice in recent years

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Acta Oceanologica Sinica 2021年第7期40卷 119-128页

作者： Guanghua Hao Hui Shen Yongming Sun Chunhua Li Key Laboratory of Marine Hazards Forecasting National Marine Environmental Forecasting CenterMinistry of Natural ResourcesBeijing 100081China Key Laboratory of Physical Oceanography College of Oceanic and Atmospheric SciencesOcean University of ChinaQingdao 266100China Pilot National Laboratory for Marine Science and Technology(Qingdao) Qingdao 266237China

A 41-year Antarctic sea ice concentration(SIC)dataset derived from satellite passive microwave radiometers during the period of 1979–2019 has been used to analyze sea ice changes in recent decades.The trends of SIC and sea ice extent(SIE)are calculated during the periods of 1979–2019,1979–2013,and 2014–2019.The trends show regionally dependent features.The SIC shows an increasing trend in most of the regions except the Bellingshausen Sea and Amundsen Sea(BA)during 1979–2019 and 1979–2013.The SIE trend shows a decreasing or decelerating trend in the period of 1979–2019((6835±2210)km^(2)/a)compared with the 1979–2013 period((18600±2203)km^(2)/a).In recent years(2014–2019),the SIC and SIE have exhibited decreasing trends(–(34567±3521)km^(2)/month),especially in the Weddell Sea(WS)and Ross Sea(RS)during summer and autumn.The trends are related to regionally dependent causes.The analyses show that the SIC and SIE decreased in response to the warming trend of 2 m air temperature(T_(a-2m))and have exhibited a good relationship with T_(a-2m) in summer and autumn in recent years.The sea ice decrease in the Antarctic is mainly caused by increases in absorbed energy and southward energy transportation in recent years,such as the increase in gained solar radiation and moist static energy from the south,which demonstrate notable regional characteristics.In the WS region,the local positive feedback from the additional absorbed solar radiation,resulting in warmer air and reduced sea ice,is the main reason for the sea ice decrease in recent years.The increase in southward energy transport has also favored a decrease in sea ice.In the RS region,the increase in southward-transported moist static energy has contributed to the decrease in sea ice,and the increases in cloud cover and longwave radiation have prevented sea ice growth.

关键词： sea ice Antarctic decreasing atmosphere

Trimetallic FeCoNi disulfide nanosheets for CO_(2)-emission-free methanol conversion

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Chinese Chemical Letters 2022年第2期33卷 1006-1010页

作者： Yunan Yi Junshan li chunhua Cui Molecular Electrochemistry Laboratory Institute of Fundamental and Frontier SciencesUniversity of Electronic Science and Technology of ChinaChengdu 610054China Yangtza Delta Region Institute(Huzhou) University of Electronic Science and Technology of ChinaHuzhou 313001China Department of Mechanical Engineering National University of SingaporeSingapore 117575Singapore

The electrocatalytic methanol conversion is of importance in direct methanol fuel cell,biomass reform-ing,and hydrogen generation.To achieve a“carbon-neutral”target,CO_(2)byproducts derived from biofuels should be mitigated.In contrast to the complete oxidation of methanol to CO_(2),the selective oxidation of methanol to formate is a CO_(2)-emission-free route without the generation of toxic CO intermediates.Herein,we present a highly active catalyst based on transition-metal disulfide nanosheet arrays sup-ported on Ni foam for methanol conversion.Through composition screening,we find that the FeCoNi disulfide nanosheet exhibits a highly efficient and selective methanol-to-formate conversion.The surface reconstruction of this catalyst allows us to produce 0.66 mmol cm^(−2)h^(−1)of formate at low potential(1.40 V)with high faradaic efficiency of>98%.This work offers a substantial composition tuning strat-egy to construct noble-metal-free active multi-metal sites for CO_(2)-emission-free conversion of methanol to value-added formate.

关键词： Nanosheet Trimetallic catalyst Transition-metal sulfide Electrocatalysis Methanol oxidation Formate

Optimizing environmental insulation thickness of buildings with CHP-based district heating system based on amount of energy and energy grade

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Frontiers in Energy 2022年第4期16卷 613-628页

作者： Yumei ZHANG Pengfei JIE Chunhua LiU Jing li School of Mechanical Engineering Beijing Institute of Petrochemical TechnologyBeijing 102617China Engineering and Technology R&D Center of Clean Air Conditioning in Colleges of Shandong Shandong Huayu University of TechnologyDezhou 253000China China Environmental Resources Technology Co. LtdBeijing 100012China

The increase of insulation thickness(IT)results in the decrease of the heat demand and heat medium temperature.A mathematical model on the optimum environmental insulation thickness(OEIT)for minimizing the annual total environmental impact was established based on the amount of energy and energy grade reduction.Besides,a case study was conducted based on a residential community with a combined heat and power(CHP)-based district heating system(DHS)in Tianjin,China.Moreover,the effect of IT on heat demand,heat medium temperature,exhaust heat,extracted heat,coal consumption,carbon dioxide(CO_(2))emissions and sulfur dioxide(SO_(2))emissions as well as the effect of three types of insulation materials(i.e.,expanded polystyrene,rock wool and glass wool)on the OEIT and minimum annual total environmental impact were studied.The results reveal that the optimization model can be used to determine the OEIT.When the OEIT of expanded polystyrene,rock wool and glass wool is used,the annual total environmental impact can be reduced by 84.563%,83.211%,and 86.104%,respectively.It can be found that glass wool is more beneficial to the environment compared with expanded polystyrene and rock wool.

关键词： optimum environmental insulation thickness heat medium temperature energy grade extracted heat exhaust heat

The elphbolt ab initio solver for the coupled electron-phonon Boltzmann transport equations

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npj Computational Materials 2022年第1期8卷 236-244页

作者： Nakib H.Protik Chunhua Li Miguel Pruneda David Broido Pablo Ordejón Catalan Institute of Nanoscience and Nanotechnology(ICN2) CSIC and BISTCampus Bellaterra8193BarcelonaSpain Department of Physics Boston CollegeChestnut HillBostonMA02467USA

elphbolt is a modern Fortran (2018 standard) code for efficiently solving the coupled electron–phonon Boltzmann transport equations from first principles.Using results from density functional and density functional perturbation theory as inputs,it can calculate the effect of the non-equilibrium phonons on the electronic transport (phonon drag) and non-equilibrium electrons on the phononic transport (electron drag) in a fully self-consistent manner and obeying the constraints mandated by thermodynamics.It can calculate the lattice,charge,and thermoelectric transport coefficients for the temperature gradient and electric fields,and the effect of the mutual electron–phonon drag on these transport properties.The code fully exploits the symmetries of the crystal and the transport-active window to allow the sampling of extremely fine electron and phonon wave vector meshes required for accurately capturing the drag phenomena.The coarray feature of modern Fortran,which offers native and convenient support for parallelization,is utilized.The code is compact,readable,well-documented,and extensible by design.

关键词： properties phonon equations

Dynamic-stiffening-induced aggravated cracking behavior driven by metal-substrate-constraint in a coating/substrate system

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Journal of Materials Science & Technology 2021年第6期65卷 154-163页

作者： Guangrong li chunhua Tang Guanjun Yang State Key Laboratory for Mechanical Behavior of Materials School of Materials Science and EngineeringXi'an Jiaotong UniversityXi'an710049China

Air plasma sprayed thermal barrier coatings(APS-TBCs)saw their wide application in high-temperaturerelated cutting-edge fields.The lamellar structure of APS-TBCs provides a significant advantage on thermal insulation.However,short life span is a major headache for APS-TBCs.This is highly related to the property changes and passive behaviors of the coatings during thermal service.Herein,a finite element model was developed to investigate the dynamic stiffening and substrate constraint on total spallation process.Results show that the stiffening accelerates the crack propagation of APS-TBCs.The driving force for crack propagation,which is characterized by strain energy release rate(SERR),is significantly enlarged.Consequently,the crack starts to propagate when the SERR exceeds the fracture toughness.In addition,the changing trends of SERR and crack propagation features are highly associated with temperatures.A higher temperature corresponds to more significant effect of stiffening on substrate constraint.In brief,temperature-dependent stiffening significantly aggravates the substrate constraint effect on APS-TBCs,which is one of the major causes for the spallation.Given that,lowering stiffening degree is essential to maintain high strain tolerance,and to further extend the life span of APS-TBCs.This understanding contributes to the development of advanced TBCs in future applications.

关键词： Thermal barrier coatings Substrate constraint Stiffening Crack propagation Structural design

Applications of EMD to analyses of high-frequency beachface responses to Storm Bebinca in the Qing’an Bay,Guangdong Province,China

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Acta Oceanologica Sinica 2022年第5期41卷 147-162页

作者： Taihuan Hu Zhiqiang li chunhua Zeng Gaocong li Huiling Zhang College of Electronic and Information Engineering Guangdong Ocean UniversityZhanjiang524088China South China Sea Resources Big Data Center Southern Marine Science and Engineering Guangdong Laboratory(Zhanjiang)Zhanjiang524000China College of Ocean Engineering Guangdong Ocean UniversityZhanjiang524088China

On average,five to six storms occur in the Qiongzhou Strait every year,causing significant damage to coastal geomorphology and several property losses.Tropical Storm Bebinca is the most unusual and complex storm event that has occurred in this region over the last 10 years.To detect the high-frequency beachface responses to the storm,a pressure sensor was deployed in the surf zone to record the free sea surface height,and the heights of grid pile points on the beachface were measured manually to determine beach elevation changes during this storm.Empirical Mode Decomposition and related analysis techniques were used to analyze the high-frequency topography and wave data.The results showed that:(1)the beachface response process occurred in three stages.The first stage was the rapid response stage,wherein the spring tide berm began to erode significantly,and the front edge of the beach berm reacted closely.The two beach sections resisted the harmful energy of the main storm.In the second stage,the beach slope increased after a large sediment loss on the beach berm and its front edge.To adapt to the storm energy,the beach at the low tide line began to erode,and the beach slope decreased.In the third stage,after the storm turned,the wave energy was significantly attenuated,and the beach berm eroded to resist the residual wave energy.The beachface began to oscillate and recover.(2)The main wave surface was the superimposed product of a few internal mode functions.Similar results were observed in beachface changes.High-frequency driving factors determine the local characteristics of beach evolution,and low-frequency driving factors determine the beach evolution trend.(3)The response of sediment to the storm was not a single sea-transportation,but a single-or two-way conversion driven by factors such as wave energy,swash flow,and secondary wave breaking.(4)TheΩ-RTR model is not completely applicable to beach states that undergo rapid changes during storms.Therefore,it is necessary to carry out further research on beach

关键词： EMD internal mode functions Bebinca beach response wave energy beach state

Design and test of the motion system for HEPS storage ring horizontal collimator

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Radiation Detection Technology and Methods 2023年第4期7卷 484-492页

作者： liuxu Zong Haijing Wang Chunhua Li Guangyi Tang Huamin Qu Shang Lu Institute of High Energy Physics Chinese Academy of ScienceBeijing100049China University of Chinese Academy of Science Beijing100049China

Background Collimators in the storage ring of high-energy photon source(HEPS)are used to localize the beam loss,making it possible to set local radiation shields.The motion system of the collimator is used to adjust the position of the movable jaws for controlling the beam loss precisely.Moreover,dump mode of the collimator increases the risk of jaw damage from beam heat deposition.According to the requirements of motion accuracy and the severe working condition of the collimators,a new design of a two-axis motion system for the movable jaws is proposed,realizing high-precision control and extending the lifetime.Purpose The purpose of this paper is to introduce the designing scheme of the motion system for HEPS storage ring horizontal collimators,including the analyses of the key components,the structure design of the motion system and test results of the prototype.Method Temperature excursions of the movable jaw are calculated theoretically and analyzed by ANSYS,respectively.The motion accuracy of the system is measured by coordinate measuring machine.Result The temperature excursion is simulated as 1883 K while using graphite as the absorbing material at dump mode.The motion system consists of a mobile slide for aperture adjustment and a manual wedge jack for vertical adjustment.The average coupled deviation in horizontal direction of the wedge jack is 0.031 mm,while the maximum positioning deviation of the slide is 0.014 mm,both having good repeatability and being compensable.Conclusion Test results of the prototype indicate that the new design of the motion system is applicable to the horizontal collimator in HEPS storage ring.The problem of the jaw rotation in the horizontal movement is found,and the solution is given.

关键词： Collimator Dump mode Structure design Motion accuracy

Interferon regulatory factor 3-CL,an isoform of IRF3,antagonizes activity of IRF3

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Cellular & Molecular Immunology 2011年第1期8卷 67-74页

作者： Chunhua Li lixin Ma Xinwen Chen State Key Laboratory of Virology Wuhan Institute of VirologyChinese Academy of SciencesWuhanChina Institute of Biochemistry and Molecular Biology Hubei UniversityWuhanChina Graduate School of the Chinese Academy of Sciences BeijingChina

Interferon regulatory factor 3(IRF3),one member of the IRF family,plays a central role in induction of type I interferon(IFN)and regulation of apoptosis.Controlled activity of IRF3 is essential for its functions.During reverse transcription(RT)-PCR to clone the full-length open reading frame(ORF)of IRF3,we cloned a full-length ORF encoding an isoform of IRF3,termed as IRF3-CL,and has a unique carboxyl-terminus of 125 amino acids.IRF3-CL is ubiquitously expressed in distinct cell lines.Overexpression of IRF3-CL inhibits Sendai virus(SeV)-triggered induction of IFN-β and SeV-induced and inhibitor of NF-kB kinase-e(IKKε)-mediated nuclear translocation of IRF3.When IKKε is overexpressed,IRF3-CL is associated with IRF3.These results suggest that IRF3-CL,the alternative splicing isoform of IRF-3,may function as a negative regulator of IRF3.

关键词： interferon regulatory factor 3 negative regulation splicing variant