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Spatial Patterns and Interspecific Associations of Three Canopy Species at Different Life Stages in a Subtropical Forest, China

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Journal of Integrative Plant Biology 2008年第9期50卷 1140-1150页

作者： Lin Li Shi-Guang Wei Zhong-Liang Huang wan-hui ye Hong-Lin Cao South China Botanical Garden Chinese Academy of Sciences Guangzhou 510650 China Graduate University of Chinese Academy of Sciences Beijing 100049 China Applied Science and Technology College Guilin University of Electronic Technology Guilin 541004 China

Spatial patterns of species at different life stages are an important aspect for understanding causal mechanisms that facilitate species co-existence. Using Ripley＇s univariate L（t） and bivariate L12（t） functions, we analyzed the spatial patterns and *** associations of three canopy species at different life history stages in a 20-ha subtropical forest plot in Dinghushan Nature Reserve. Based on diameter at breast height （DBH）, four life stages were distinguished. Castanopsis chinensis and Schima superba showed a unimodal DBH distribution. Engelhardtia roxburghiana showed a bimodal curve. L（t） function analysis showed significantly aggregated distributions of all three species at later life stages and random distribution at early life stages at some scales. From the analysis of L12（t） function, the results showed the positive association was a dominant pattern for most species pairs at most scales but the intensity of association decreases with the increase of life stages. Juveniles of the three species had no negative intra- and interspecific associations with the older life stages. Only premature trees were suppressed by overmature trees at some scales. Considering these results, we found three canopy-dominant species that lacked regeneration. There was no direct competition occurring between understorey individuals. Young trees can grow well under conspecific species with two other species. Longevity and lack of regeneration led to a large number of trees stored in mature and overmature stages, therefore, intra- and inter-competition can be strong at later life stages.

关键词： Castanopsis chinensis Dinghushan Engelhardtia roxburghiana interspecific association Schima superba spatial pattern.

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Developing phase of China's system of nature reserves in perspective

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Forestry Studies in China 2013年第4期15卷 340-348页

作者： Xue-Jun OUYANG wan-hui ye Marc HOCKINGS Chung-Lim LUK Zhong-Liang HUANG Dinghushan National Nature Reserve South China Botanical GardenChinese Academy of Sciences School of Geography Planning and Environmental Management University of Queensland Earthwatch Institute 13/F Breakthrough Centre

Up until 2009, 2541 nature reserves had been established in China. However, the process of developing this system of nature reserves was not quite smooth. Various kinds of information related to nature reserves, such as annual growth, the type of nature reserves established, motives behind building a nature reserve, legal instructions and the constitution of government sectors, were collected and analyzed in order to highlight the characteristics of the development of our nature reserve system. As a result, we identify three phases and their characteristics, i.e., the initial phase from 1956 to 1978, the establishment phase from 1979 to 1996 and the management standardization phase from 1997 to 2009, could be clearly identified. It is suggested that since the establishment of this comprehensive structural framework in China, the system should be entering a new developing phase. We recommend that more attentions should be paid on how to guarantee effective management and how nature reserves are able to maintain their value and fulfill their objectives in the future.

关键词： system of nature reserves China developing phase nature conservation jurisprudence types of nature reSerVe

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A Review on Vibration Control of Multiple Cylinders Subjected to FlowInduced Vibrations

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China Ocean Engineering 2024年第2期38卷 183-197页

作者： XU wan-hai MA ye-xuan State Key Laboratory of Hydraulic Engineering Intelligent Construction and Operation Tianjin UniversityTianjin 300350China Institute of Mechanics Chinese Academy of SciencesBeijing 100190China

The fatigue damage caused by flow-induced vibration(FIV)is one of the major concerns for multiple cylindrical structures in many engineering *** FIV suppression is of great importance for the security of many cylindrical *** active and passive control methods have been employed for the vibration suppression of an isolated cylinder undergoing vortex-induced vibrations(VIV).The FIV suppression methods are mainly extended to the multiple cylinders from the vibration control of the isolated *** to the mutual interference between the multiple cylinders,the FIV mechanism is more complex than the VIV mechanism,which makes a great challenge for the FIV *** efforts have been devoted to vibration suppression of multiple cylinder systems undergoing FIV over the past two *** control methods,such as helical strakes,splitter plates,control rods and flexible sheets,are not always effective,depending on many influence factors,such as the spacing ratio,the arrangement geometrical shape,the flow velocity and the parameters of the vibration control *** FIV response,hydrodynamic features and wake patterns of the multiple cylinders equipped with vibration control devices are reviewed and *** FIV suppression efficiency of the vibration control methods are analyzed and compared considering different influence *** research on the FIV suppression of multiple cylinders is suggested to provide insight for the development of FIV control methods and promote engineering applications of FIV control methods.

关键词： flow-induced vibration vibration control multiple cylinders tandem side-by-side staggered

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Microstructure evolution and mechanical properties of brazing joint for ultra-thin-walled Inconel 718 considering grain size effect and brazing temperature

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Chinese Journal of Aeronautics 2024年第2期37卷 541-556页

作者： Rui ZHAO Yueshuai SONG hui KANG Min wan School of Mechanical Engineering and Automation Beihang UniversityBeijing 100191China Jiangxi Research Institute of Beihang University Jiangxi 330000China

The systematic investigation of the mechanical properties and microstructure evolution process of ultra-thin-walled Inconel 718 capillary brazing joints is of great significance because of the exceptionally high demands on its *** achieve this objective,this study investigates the impact of three distinct brazing temperatures and five typical grain sizes on the brazed joints’mechanical properties and microstructure evolution *** evolution analysis was conducted based on Electron Back Scatter Diffraction(EBSD),Scanning Electron Microscopy(SEM),X-Ray Diffraction(XRD),High-Resolution Transmission Electron Microscopy(HRTEM),and Focused Ion Beam(FIB).Besides,the mechanical properties and fracture behavior were studied based on the uniaxial tension tests and in-situ tension *** findings reveal that the brazing joint’s strength is higher for the fine-grain capillary than the coarse-grain one,primarily due to the formation of a dense branch structure composed of G-phase in the brazing *** effects of grain size,such as pinning and splitting,are amplified at higher brazing ***,micro-cracks initiate around brittle intermetallic compounds and propagate through the eutectic zone,leading to a cleavage fracture *** fracture stress of fine-grain specimens is higher than that of coarse-grain due to the complex micro-crack ***,this study contributes significantly to the literature by highlighting the crucial impact of grain size on the brazing properties of ultra-thin-walled Inconel 718 structures.

关键词： EYWORDS Ultra-thin-walled structure Brazing Inconel 718 Grain size effect Brazing temperature

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Phylogenetic and climatic constraints drive flowering phenological patterns in a subtropical nature reserve

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Journal of Plant Ecology 2015年第2期8卷 187-196页

作者： Nan-Cai Pei WJohn Kress Bu-Feng Chen David LErickson Khoon Meng Wong Jin-Long Zhang wan-hui ye Zhong-Liang Huang Dian-Xiang Zhang Forest Ecosystem Station of the Pearl River Delta State Forestry AdministrationResearch Institute of Tropical ForestryChinese Academy of Forestry682 Guangshan Road 1Tianhe DistrictGuangzhou 510520China Department of Botany MRC-166National Museum of Natural HistorySmithsonian InstitutionP.O.Box 37012WashingtonDC 20013-7012USA Singapore Botanic Gardens 1 Cluny RoadSingapore 259569Singapore Flora Conservation Department Kadoorie Farm and Botanic GardenLam Kam RoadTai PoNTHongkongChina South China Botanical Garden Chinese Academy of Sciences723 Xingke RoadTianhe DistrictGuangzhou 510650China

Aims Exploring flowering patterns and detecting processes are essential when probing into the nature of reproductive traits during the life history and the interactions among different evolutionary *** patterns are believed to be influenced by many factors,but quantifying these impacts at the community-level remains poorly *** We investigated the flowering patterns based on long-term her-barium records in a given area from subtropical forest regions in southern *** obtained 5258 herbarium voucher specimens collected from the Dinghushan National Nature reserve(DNNr)belonging to 166 families,943 genera and 2059 species and exam-ined the month when each species was flowering during the period *** Findings The results showed that plants flowered sequentially almost through-out the whole year,showing the characteristics of subtropical evergreen broad-leaved *** spectrums of the entire flora and the four life forms exhibited a clear unimodality that is probably typical of subtropical forest *** pat-terns of the DNNr were positively correlated with mean rainfall,mean air temperature and mean sunshine *** flowering dates of the 38 large species-rich families ranged from early april to late august;25 families exhibited significant unimodal distribution patterns,whereas the remaining families were unclear or *** flowering dates of the 10 most species-rich genera ranged from middle may to later *** the results are consist-ent with climatic factors playing a general role in flowering patterns,median flowering dates varied significantly among species-rich families and genera,suggesting that phylogenies could provide spe-cific constraints in subtropical forests.

关键词： environmental driver flowering phenology phylogenetic effect reproductive trait subtropical forest

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Noninvasive beam diagnosis based on the TM_(010)mode

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Nuclear Science and Techniques 2024年第7期35卷 115-125页

作者： Chuang-ye Song Wen-hui Huang Department of Engineering Physics Tsinghua University BeijingBeijing100084China of Education Beijing100084China

A resonant cavity based on the TM_(010)mode is an effective tool for noninvasive beam characterization. This technique has the advantages of a high signal-to-noise ratio, compact structure, and is related to multiple parameters compared with other beam monitors. In this study, high-precision measurements of the bunch charge, arrival time, bunch length, and energy parameters based on the TM_(010)mode are discussed. A cavity beam arrival time monitor(BAM) utilizing a phase cavity has been widely used in many facilities. Regarding bunch-length measurements, the influence of the beam energy, beam offset,and longitudinal spectrum on the TM_(010)mode are carefully considered to reduce errors, and the theoretical resolution of two cavities with different frequencies is analyzed. Owing to the dependence of the beam velocity of the beam loss factor, this method can also be used for the detection low beam energy using two cavities with the same frequency but different cavity lengths. A set of three cavities with different lengths and frequencies of 1.902 and 11.424 GHz is presented for measuring the four aforementioned parameters.

关键词： TM_(010)mode Noninvasive diagnosis Beam length Low energy

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Tuning the surface electronic structure of noble metal aerogels to promote the electrocatalytic oxygen reduction

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Journal of Energy Chemistry 2024年第2期89卷 557-564,I0013页

作者： Hongxing Yuan Wei Gao Xinhao wan Jianqi ye Dan Wen State Key Laboratory of Solidification Processing School of Materials Science and EngineeringNorthwestern Polytechnical UniversityXi’an 710072ShaanxiChina

The sluggish kinetics of the oxygen reduction reaction(ORR)is the bottleneck for various electrochemical energy conversion *** the electronic structure of electrocatalysts by ligands has received particular attention in deriving valid ORR ***,the surface electronic structure of Ptbased noble metal aerogels(NMAs)was modulated by various organic ligands,among which the electron-withdrawing ligand of 4-methylphenylene effectively boosted the ORR *** calculations suggested the smaller energy barrier for the transformation of O^(*) to OH^(*) and downshift the d-band center of Pt due to the interaction between 4-methylphenylene and the surface metals,thus enhancing the ORR intrinsic *** Pt3Ni and Pt Pd aerogels with 4-methylphenylene decoration performed significant enhancement in ORR activity and durability in different ***,the 4-methylphenylene modified Pt Pd aerogel exhibited the higher halfwave potential of 0.952 V and the mass activity of 10.2 times of commercial Pt/*** work explained the effect of electronic structure on ORR electrocatalytic properties and would promote functionalized NMAs as efficient ORR electrocatalysts.

关键词： Noble metal aerogels Surface electronic structure ORR Electrocatalyst Organic ligands

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Targeting tau in Alzheimer's disease:from mechanisms to clinical therapy

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Neural Regeneration Research 2024年第7期19卷 1489-1498页

作者： Jinwang ye Huali wan Sihua Chen Gong-Ping Liu Shenzhen Key Laboratory of Marine Biotechnology and Ecology College of Life Sciences and OceanographyShenzhen UniversityShenzhenGuangdong ProvinceChina Department of Laboratory Medicine Guangdong Provincial People’s Hospital(Guangdong Academy of Medical Sciences)Southern Medical UniversityGuangzhouGuangdong ProvinceChina Co-innovation Center of Neurodegeneration Nantong UniversityNantongJiangsu ProvinceChina Department of Pathophysiology School of Basic Medicine and the Collaborative Innovation Center for Brain ScienceKey Laboratory of Ministry of Education of China and Hubei Province for Neurological DisordersTongji Medical CollegeHuazhong University of Science and TechnologyWuhanHubei ProvinceChina

Alzheimer’s disease is the most prevalent neurodegenerative disease affecting older *** features of Alzheimer’s disease include extra cellular aggregation of amyloid-βplaques and the accumulation of neurofibrillary tangles,fo rmed by tau protein,in the *** there are amyloid-β-ta rgeting therapies for the treatment of Alzheimer’s disease,these therapies are costly and exhibit potential negative side *** evidence suggests significant involvement of tau protein in Alzheimer’s disease-related *** an important microtubule-associated protein,tau plays an important role in maintaining the stability of neuronal microtubules and promoting axonal *** fact,clinical studies have shown that abnormal phosphorylation of tau protein occurs before accumulation of amyloid-βin the *** therapeutic strategies targeting tau protein have begun to emerge,and are considered possible methods to prevent and treat Alzheimer’s ***,abnormalities in post-translational modifications of the tau protein,including aberrant phosphorylation,ubiquitination,small ubiquitin-like modifier(SUMO)ylation,acetylation,and truncation,contribute to its microtubule dissociation,misfolding,and subcellular *** causes mitochondrial damage,synaptic impairments,gliosis,and neuroinflammation,eventually leading to neurodegeneration and cognitive *** review summarizes the recent findings on the underlying mechanisms of tau protein in the onset and progression of Alzheimer’s disease and discusses tau-targeted treatment of Alzheimer’s disease.

关键词： acetylation Alzheimer’s disease cognitive deficits gliosis mitochondria damage neuroinflammation phosphorylation synaptic impairments tau tau immunotherapy

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Role of phosphorus on the biogeochemical behavior of cadmium in the contaminated soil under leaching and pot experiments

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Journal of Environmental Sciences 2024年第3期137卷 488-499页

作者： hui Jia YifanWu Mengqi Zhang Jinhui ye Daolin Du He wang Institute of Environment and Ecology School of Emergency ManagementJiangsu UniversityZhenjiang 212013China School of the Environment and Safety Engineering&Institute of Environment and Ecology Jiangsu UniversityZhenjiang 212013China Jiangsu Collaborative Innovation Center of Technology and Material of Water Treatment Suzhou University of Science and TechnologySuzhou 215009China Xuzhou Medical University Affiliated HospitalXuzhou 221004China

Phosphorus(P)is involved in various biochemical reactions in plant growth,so it is beneficial to plants growing in soils contaminated by metals,including cadmium(Cd).However,few studies have reported on the mechanistic roles of P in mitigating Cd toxicity to ryegrass root,and especially in alleviating the disruption of the mitochondrial function of living *** this study,the physiological and biochemical mechanisms associated with ryegrass growth under various Cd and P treatments were investigated using leaching and pot *** concentration of Cd in soil leachates showed a significantly positive relationship with redox potential(P<0.05),but negative relationship(P<0.05)with leachate pH values and dissolved organic carbon(DOC),indicating that exogenous P addition(as H_(2)PO_(4)*)may decrease Cd leaching from contaminated *** to the control(without P addition),the cumulative Cd content was reduced by 53.3%and 64.5%in the soil leachate with exogenous P application(20 mg/L and 80 mg/L),***,application of P decreased the Cd concentrations in the symplastic fractions and increased the Cd concentrations in the apoplastic fractions in root tips,which may help to alleviate Cd stress to the ***,exogenous P was found to play a positive role in mitochondrial function and Ca^(2+)variation in root cells under Cd stress,which provides novel insights into the mechanisms of exogenous P in alleviating plant Cd injury.

关键词： Phosphorus Cadmium stress Protoplast Biogeochemical behavior Mitochondrial function

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Vibration Suppression for Active Magnetic Bearings Using Adaptive Filter with Iterative Search Algorithm

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CES Transactions on Electrical Machines and Systems 2024年第1期8卷 61-71页

作者： Jin-hui ye Dan Shi Yue-Sheng Qi Jin-hui Gao Jian-Xin Shen IEEE Department of Electrical Engineering Zhejiang UniversityHangzhou 310027China CES and IEEE

Active Magnetic Bearing(AMB) is a kind of electromagnetic support that makes the rotor movement frictionless and can suppress rotor vibration by controlling the magnetic force. The most common approach to restrain the rotor vibration in AMBs is to adopt a notch filter or adaptive filter in the AMB controller. However, these methods cannot obtain the precise amplitude and phase of the compensation current. Thus, they are not so effective in terms of suppressing the vibrations of the fundamental and other harmonic orders over the whole speed range. To improve the vibration suppression performance of AMBs,an adaptive filter based on Least Mean Square(LMS) is applied to extract the vibration signals from the rotor displacement signal. An Iterative Search Algorithm(ISA) is proposed in this paper to obtain the corresponding relationship between the compensation current and vibration signals. The ISA is responsible for searching the compensating amplitude and shifting phase online for the LMS filter, enabling the AMB controller to generate the corresponding compensation force for vibration suppression. The results of ISA are recorded to suppress vibration using the Look-Up Table(LUT) in variable speed range. Comprehensive simulations and experimental validations are carried out in fixed and variable speed range, and the results demonstrate that by employing the ISA, vibrations of the fundamental and other harmonic orders are suppressed effectively.

关键词： Active Magnetic Bearing(AMB) Adaptive filter Iterative search algorithm Least mean square(LMS) Vibration suppression

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