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An unprotected vulnerable relict subtropical conifer-Keteleeria evelyniana: Its forests, populations, growth and endangerment by invasive alien plant species in China

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Plant Diversity 2024年第5期46卷 648-660页

作者： Cindy Q.Tang Min-Rui Du Huan-chong wang You-Cai Shi Jia-Le Zeng Shu-Li Xiao Peng-Bin Han Jian-Ran Wen Shi-Qian Yao Ming-Chun Peng chong-yun wang Yong-Ping Li Jordi López-Pujol Institute of Ecology and Geobotany College of Ecology and Environmental ScienceYunnan UniversityBuilding#3Guozhong DalouDongwaihuan South RoadUniversity TownChenggong New DistrictKunming 650504YunnanChina College of Life Sciences Yunnan UniversityShengming Kexueyuan Building#2Chenggong CampusDongwaihuan South RoadUniversity TownChenggong New DistrictKunming 650504YunnanChina College of Natural Resources Yunnan UniversityChenggong CampusDongwaihuan South RoadUniversity TownChenggong New DistrictKunming 650504YunnanChina Botanic Institute of Barcelona(IBB CSIC-CMCNC)Passeig del Migdia s/nBarcelona 08038CataloniaSpain Escuela de Ciencias Ambientales Universidad Espíritu Santo(UEES)Samborondon 091650Ecuador

Relict subtropical coniferous forests in China face severe fragmentation,resulting in declining populations,and some are under significant threat from invasive alien *** the crucial importance of understanding forest dynamics,knowledge gaps persist,particularly regarding the impact of invasive plants on vulnerable natives like Keteleeria *** this study,we investigated the impact of invasive plants on the regeneration of forests dominated by ***,a subtropical relict species in southwestern *** this purpose,we characterized forest dynamics of 160 forest plots featuring *** as the primary dominant species and determined whether the presence of invasive plants was correlated with regeneration of *** identified four distinct forest types in which *** was *** found that radial growth of *** trees is faster in younger ageclasses today than it was for older trees at the same *** population structure of *** in each forest type exhibited a multimodal age-class ***,three forest types lacked established saplings younger than 10 years old,a situation attributed to the dense coverage of the invasive alien Ageratina *** invasive species resulted in a reduction of understory species ***,our analysis uncovered a significant negative correlation in phylogenetic relatedness(net relatedness index)between native and invasive alien plant species in eastern *** suggests closely related invasive species face heightened competition,hindering successful *** together,our findings indicate that successful establishment and habitat restoration of *** seedling/saplings require effective measures to control invasive plants.

关键词： Keteleeria evelyniana Age structure Regeneration Species diversity Invasive alien species Phylogenetic relatedness

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Square-Wave Drive for Synchronous Reluctance Machine and its Torque Ripple Analysis

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CES Transactions on Electrical Machines and Systems 2021年第4期5卷 273-283页

作者： Jian-Xin Shen Shun Cai Dong-Min Miao Dan Shi Jacek Gieras yun-chong wang the College of Electrical Engineering Zhejiang UniversityZhejiang Provincial Key Laboratory of Electrical Machine SystemsHangzhou310027China the School of Electrical and Electronic Engineering Nanyang Technological University639798Singapore the Department of Electrical Engineering UTP University of Science and TechnologyBydgoszcz85-796Poland

Synchronous reluctance machine(SynRM)can be perceived as a special type of permanent magnet synchronous machine(PMSM),and shares similar control method,*** sine-wave current drive with sinusoidal phase *** this paper,square-wave drive,which is employed for permanent magnet brushless(BLDC)motors,is employed for the SynRM,in order to economically reduce the cost of rotor position *** is revealed that the torque density and efficiency are slightly sacrificed,whereas torque ripple is deteriorated,proving the SynRM with square-wave drive still promising for the cost-sensitive application if torque ripple is not considered as a critical *** further investigate the additional pulsating torque under square-wave drive,mathematical model based on a-b-c phase inductance and d-q axis inductance are established,together with the time-stepping FE calculated *** is concluded that the harmonics in the currents tend to cause non-sinusoidal variation of the magnetic reluctance,which can be represented as additional inductance *** harmonics of the current and inductance interact with each other,thus undesirable torque ripple components are produced.

关键词： Synchronous reluctance machine pulsating torque square-wave drive inductance magnetic saturation

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Species richness, forest types and regeneration of Schima in the subtropical forest ecosystem of yunnan, southwestern China

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Forest Ecosystems 2020年第3期7卷 443-461页

作者： Cindy QTang Peng-Bin Han Shuaifeng Li Li-Qin Shen Diao-Shun Huang yun-Fang Li Ming-Chun Peng chong-yun wang Xiao-Shuang Li Wei Li Wei wang Zhi-Ying Zhang Institute of Ecology and Geobotany College of Ecology and Environmental ScienceYunnan UniversityKunming650504China Research Institute on Resource Insects Chinese Academy of ForestryKunming650224China Caojian Forest Farm of yunlong Forestry Bureau Yunlong County672711YunnanChina yunnan Academy of Forestry Kunming650201China Tibet Agriculture and Animal Husbandry College Linzhi860000China

Background: Schima genus of Theaceae is confined to subtropics and tropics of South, East and Southeast *** species of Schima are distributed in subtropical China. Many of them appear as dominant canopy species in the subtropical forests. To date, Schima species richness distribution patterns of China have remained ***, there has been a longtime debate as to whether forests dominated by Schima species are early or late successional forests. We aim to clarify Schima species richness patterns and these species' roles in the forest succession and regeneration dynamics of the subtropical ecosystem in yunnan Province, ***: We mapped Schima species richness distribution patterns in China. Based on 71 vegetation plots, we analyzed forest characteristics, population structure, and regeneration dynamics of Schima species in ***: yunnan was found to harbor the greatest richness and the highest rarity-weighted richness of Schima species in the subtropical regions of China. We classified five primary and six secondary forest types containing Schima species as one of dominants. yunnan had the high floristic diversity and varying stand structure of forests containing Schima species. The Schima species studied generally had a sporadic regeneration type and a long lifespan. Four species(Schima argentea, Schima villosa, Schima sinensis, Schima sericans) were shade-intolerant. But three species(Schima noronhae, Schima khasiana and Schima wallichii) were considered as bi-modal type species having shade-intolerant and shade-tolerant traits. Schima noronhae was seen to be a top dominant in late successional forests, while S. wallichii was found as a top-dominant in early or middle or late successional forests. ***, Schima villosa, Schima sinensis usually appeared as a top dominant in early or middle successional secondary forests, though they also presented as a second dominant in late-successional forests. Schima argentea and Schima se

关键词： Forest structure Regeneration dynamics Schima Species richness Forest succession yunnan

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Toward tunable shape memory effect of NiTi alloy by grain size engineering:A phase field study

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Journal of Materials Science & Technology 2024年第1期168卷 276-289页

作者： Bo Xu chong wang Qingyuan wang Failure Mechanics and Engineering Disaster Prevention Key Laboratory of Sichuan ProvinceSichuan UniversityChengdu 610065China Department of Mechanical Science and Engineering College of Architecture and EnvironmentSichuan UniversityChengdu 610065China Key Laboratory of Deep Underground Science and Engineering (Sichuan University)Ministry of EducationChengdu 610065China

The inelastic deformations of shape memory alloys(SMAs)always show poor controllability due to the avalanche-like martensite transformation,and the effective control for the deformation of precision de-vices has been not yet *** this work,the phase field method was used to investigate the shape memory effects(SMEs)of NiTi SMAs undergoing grain size(GS)engineering,to obtain tunable one-way and stress-assisted two-way SMEs(OWSME and SATWSME).The OWSME and SATWSME of the systems with various gradient-nanograin structures and bimodal grain structure,as well as that with geometric gradients were *** simulated results indicate that due to the GS dependences of martensite transformation and reorientation,the occurrence and expansion of martensite reorientation,martensite transformation and its reverse can be efficaciously controlled via the GS *** combining the GS engineering and geometric gradient design,since the effects of GS and stress gradient can be su-perimposed or competing,and the responses of martensite reorientation,martensite transformation and its reverse to this are different,the OWSME and SATWSME of the geometrically graded systems with various nanograin structures can exhibit different improvements in *** short,the reorienta-tion hardening modulus during OWSME is increased and the transformation temperature window during SATWSME is widened by GS engineering,indicating the improved controllability of *** optimal GS engineering schemes revealed in this work provide the basic reference and guidance for designing tun-able SMEs and producing NiTi-based driving devices catering to desired functional performance in various engineering fields.

关键词： Phase field NiTi Shape memory effect Grain size engineering Geometric gradient

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Extending the detection limit:innovations in infrared quantum dot photodetectors reaching up to 18μm

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Light(Science & Applications) 2024年第8期13卷 1445-1447页

作者： chong Wu wang Qi Jie wang Centre for OptoElectronics and Biophotonics School of Electrical and Electronic EngineeringNanyang Technological UniversitySingapore 639798Singapore Centre for Disruptive Photonic Technologies School of Physical and Mathematical SciencesNanyang Technological UniversitySingaporeSingapore

A regrowth method was used to synthesize large-sized colloidal quantum dots(CQDs).With the assistance of doping engineering,the synthesized CQD detectors demonstrate exceptional long-wavelength infrared detection performance,reaching up to 18μm,significantly extending the spectral response limit for CQD-based infrared *** detectors also achieve a reasonably high detectivity of 6.6×10^(8)Jones.

关键词： limit quantum sized

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Effect of Texture on the Grain-Size-Dependent Functional Properties of NiTi Shape Memory Alloys and Texture Gradient Design:A Phase Field Study

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Acta Mechanica Solida Sinica 2024年第1期37卷 10-32页

作者： Bo Xu Beihai Huang chong wang Qingyuan wang Failure Mechanics and Engineering Disaster Prevention Key Laboratory of Sichuan ProvinceSichuan UniversityChengdu 610065China Department of Mechanical Science and Engineering College of Architecture and EnvironmentSichuan UniversityChengdu 610065China Key Laboratory of Deep Underground Science and Engineering Ministry of EducationSichuan UniversityChengdu 610065China

Texture is inevitably introduced during the manufacturing of most NiTi shape memory alloys(SMAs),and the textured nanocrystalline NiTi has been extensively employed in ***,the effect of texture,and the joint effect of grain size(GS)and texture on the functional properties of NiTi SMAs and the corresponding microscopic mechanisms have not been clearly understood *** this work,based on the phase field method,the effect of texture on the GS-dependent functional properties of NiTi SMAs,including super-elasticity(SE),one-way shape memory effect(OWSME),and stress-assisted two-way shape memory effect(SATWSME),is investigated,and the corresponding microscopic mechanisms are ***,the samples with discrete geometrical gradients and/or texture gradients are designed to achieve graded functional *** simulation results indicate that the dependence of functional properties on texture is due to the effect of crystallographic orientation on martensite transformation and reorientation,which can lead to different inelastic *** the designed samples with texture gradients,the stress–strain responses of sheets with various textures are different,allowing for the coordination of overall deformation of the sample by combining such sheets,with varying inelastic deformation ***,the overall response of the sample differs from that without texture gradient,leading to the achievement of graded functional *** simulation results and new findings in this work contribute to a deeper understanding of the effects of texture,GS,and their interaction on the functional properties of SMAs,and provide valuable reference for the design and development of SMA-based devices with desired functional properties.

关键词： Phase field NiTi shape memory alloy Texture Grain size Functional property Texture gradient

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Forest characteristics and population structure of Glyptostrobus pensilis, a globally endangered relict species of southeastern China

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Plant Diversity 2019年第4期41卷 237-249页

作者： Cindy Q. Tang Yongchuan Yang Arata Momohara Huan-chong wang Hong Truong Luu Shuaifeng Li Kun Song Shenhua Qian Ben LePage Yi-Fei Dong Peng-Bin Han Masahiko Ohsawa Buu Thach Le Huu Dang Tran Minh Tri Dang Ming-Chun Peng chong-yun wang Institute of Ecology and Geobotany School of Ecology and Environmental ScienceYunnan UniversityDongwaihuan South RoadUniversity TownChenggong New DistrictKunmingYunnan 650504China The Nature Conservancy Society of Japan Mitoyo Bldg.2F1-16-10 ShinkawaChuo-kuTokyo 104-0033Japan Key Laboratory of Three Gorges Reservoir Region's Eco-Environment Ministry of EducationChongqing UniversityChongqing 400045China Graduate School of Horticulture Chiba University648 MatsudoChiba 271-8510Japan Institute of Botany Yunnan UniversityKunmingYunnan 650091China Southern Institute of Ecology Vietnam Academy o f Science and TechnologyHo Chi Minh CityViet Nam Research Institute of Resource Insects Chinese Academy of ForestryKunmingYunnan 650224China School o f Ecological and Environmental Sciences East China Normal UniversityShanghai 200241China Pacific Gas and Electric Company 3401 Crow Canyon RoadSan RamonCA 94583USA The Academy of Natural Science 1900 Benjamin Franklin ParkwayPhiladelphiaPA 19W3USA

The Chinese water pine Glyptostrobus pensilis is the sole surviving species of the genus Glyptostrobus. It is endemic to southern China, central Vietnam, and eastern Laos, and today it is nearly extinct in the wild. Forest community characteristics and population structure of G. pensilis in China have remained un-known up to now. We investigated six swamp forest stands and analyzed their forest community characteristics (i.e. vertical stratification, species composition, and diversity) and population structure, including the frequency distribution of DBH (diameter at breast height) and age-classes as found in Fujian Province, southeastern China. The vertical stratifications of all the forest stands were rather simple. The remaining wild specimens ranged from roughly 15 to some 357 years for an average of ca. 85 years, with only a few individuals less than 20 years old. Compared with the stands and populations of G. pensilis in Vietnam, the taxonomic compositions of the stands in the two regions were different, except for the dominant species-G. pensilis. The Shannon-Wiener index showed the overstory of each stand had much lower diversity (0.26 on average) in Fujian Province than that (1.97 on average) in Vietnam, whereas the diversity indices were about the same (around 2.41) for the understories in the two regions. Furthermore, we discovered 18 G. pensilis seedlings at the study sites in Fujian Province. This discovery demonstrates that G. pensilis regeneration is extremely poor and its populations are declining, although these populations are rela-tively healthier than those in Vietnam.

关键词： Age-class Fujian Province Glyptostrobus Regeneration Relict plant Vietnam

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Metal-organic frameworks on 3D interconnected macroporous sponge foams for large-scale water decontamination:A mini review

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Chinese Chemical Letters 2024年第5期35卷 77-84页

作者： Xiao-Hong Yi chong-Chen wang Beijing Key Laboratory of Functional Materials for Building Structure and Environment Remediation School of Environment and Energy EngineeringBeijing University of Civil Engineering and ArchitectureBeijing 100044China

Water pollution caused by global population growth,urban expansion and industrialization development is one of the urgent issues that need to be addressed in the 21st *** to now,it was challenging for metal-organic frameworks(MOFs)to be used in the actual water treatment due to that the powder MOFs suffered from difficult reuse,poor water stability and easy *** is an effective strategy to immobilize MOFs powder onto porous sponge foam carriers for accomplishing large flux,facile recycling,easy processing water treatment *** this review article,the fabrication approaches and applications of different MOFs/sponge composites were highlighted,in which the fluorescence detection of pollutants,adsorption and separation of pollutants,catalytic reduction and oxidation of pollutants were ***,the future challenges and opportunities of MOF/sponge for water treatment are proposed,aiming to provide in-depth guidance for the future design and manufacture of the immobilized MOFs onto sponge foams.

关键词： Metal-organic frameworks Sponge foam Water decontamination Adsorption Catalysis

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Forest characteristics,population structure and growth trends of threatened relict Pseudotsuga forrestii in China

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Plant Diversity 2023年第4期45卷 422-433页

作者： Cindy Q.Tang Shi-Qian Yao Peng-Bin Han Jian-Ran Wen Shuaifeng Li Ming-Chun Peng chong-yun wang Tetsuya Matsui Yong-Ping Li Shan Lu Yuan He Institute of Ecology and Geobotany College of Ecology and Environmental ScienceYunnan UniversityBuilding ShixunChenggong CampusDongwaihuan South RoadUniversity TownChenggong New DistrictKunmingYunnan 650504China College of Life Sciences Yunnan UniversityShengming Kexueyuan Building#2Chenggong CampusDongwaihuan South RoadUniversity TownChenggong New DistrictKunmingYunnan 650504China Institute of Highland Forest Science Chinese Academy of ForestryKunmingYunnan 650224China Forestry and Forest Products Research Institute Forest Research and Management OrganizationMatsunosato 1Tsukuba-shiIbaraki-ken305-8687Japan Faculty of Life&Environmental Sciences University of Tsukuba1-1-1 TennodaiTsukubaIbaraki305-8572Japan College of Natural Resources Yunnan UniversityChenggong CampusDongwaihuan South RoadUniversity TownChenggong New DistrictKunmingYunnan 650504China Forestry and Grassland Bureau of Diqing Tibetan Autonomous Prefecture 1st Floor of Government BuildingShengping TownDeqing CountyYunnan 674500China Forestry and Grassland Bureau of Weixi Lisu Autonomous County Nanjian Dao#7Baohe TownWeixi Lisu Autonomous CountyYunnan 674600China

Pseudotsuga forrestii is a relict evergreen coniferous tree species in Pinaceae endemic to *** tree numbers have greatly decreased due to deforestation,over-utilization and habitat *** we clarify *** community types,structure,species diversity,seedling recruitments and growth *** identified four *** community types:(1)Pseudotsuga forrestii-Quercus guyavifolia-Acer davidii evergreen coniferous and broad-leaved mixed forest;(2)Pseudotsuga forrestii-Pinus yunnanensis-Quercus guyavifolia evergreen coniferous and broad-leaved mixed forest;(3)Pseudotsuga forrestii evergreen coniferous forest;(4)Pseudotsuga forrestii-Abies georgei *** evergreen coniferous *** forests are characterized by both warm temperate and temperate *** diversity,Pielou evenness,Shannon-Wiener diversity indices ranged from 0.75 to 0.76,0.74-0.81,and 1.62-1.93,respectively,with no significant differences among the four forest *** forest stratification was *** canopy layer was generally 10-25 m tall,with the emergent layer reached 25-42 *** and age structures of *** showed multimodal *** maximum age *** was 570 years with a DBH of 143 *** growth of annual ring width of *** was slow,and generally decreased with age,whereas the basal area at the breast height increased with *** seedlings/saplings were mainly found in unstable *** of *** depends on moderate natural ***,we provide recommendations for *** conservation.

关键词： Pseudotsuga forrestii Community structure Species diversity Population structure Regeneration Growth trend

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Strong shock propagation for the finite-source circular blast in a confined domain

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Applied Mathematics and Mechanics(English Edition) 2024年第6期45卷 1071-1084页

作者： Qihang MA Kaileong chong Bofu wang Quan ZHOU Shanghai Key Laboratory of Mechanics in Energy Engineering Shanghai Institute of Applied Mathematics and MechanicsSchool of Mechanics and Engineering ScienceShanghai UniversityShanghai 200072China Shanghai Institute of Aircraft Mechanics and Control Shanghai 200092China

The circular explosion wave produced by the abrupt discharge of gas from a high-temperature heat source serves as a crucial model for addressing explosion phenomena in compressible *** reflection of the primary shock and its propagation within a confined domain are studied both theoretically and numerically in this *** the assumption of strong shock,the scaling law governing propagation of the main shock is *** dimensionless frequency of reflected shock propagation is associated with the confined *** numerical simulation for the circular explosion problem in a confined domain is performed for *** the influence of confinement,the principal shock wave systematically undergoes reflection within the domain until it weakens,leading to the non-monotonic attenuation of kinetic energy in the explosion fireball and periodic oscillations of the fireball volume with a certain *** simulation results indicate that the frequency of kinetic energy attenuation and the volume oscillation of the explosive fireball align consistently with the scaling law.

关键词： explosion confinement main shock frequency

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