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Distribution and dynamics of niche and interspecific association of dominant phytoplankton species in the Feiyun River basin,Zhejiang,China

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Journal of Oceanology and Limnology 2024年第4期42卷 1157-1172页

作者： Shengnan ZHU Zengchuan DONG Guobin FU Shujun WU Jinyu meng Weilin LIU Yupeng LIU xun CUI Yuejiao ZHOU College of Hydrology and Water Resources Hohai UniversityNanjing 210098China CSIRO Environment Private Bag 5Wembley WA 6913Australia Department of Agricultural and Biological Engineering Indian River Research and Education CenterUniversity of FloridaFort Pierce 34945USA Jiangxi Provincial Key Laboratory of Hydrology-Water Resources and Water Environment Nanchang Institute of TechnologyNanchang 330099China

To investigate the dominant species and interspecific association in the phytoplankton community of the Feiyun River basin in Zhejiang Province,East China,the main stream and the Shanxi Zhaoshandu Reservoir in the downstream were chosen as the study area,for which 22 sampling sites were *** was conducted in September 2021,January,May,and July *** species were identified from both quantitative samples and in-vivo *** was quantified by direct *** show that there were 98 species belonging to 6 phyla and 78 *** addition,to clarify the niches of the dominant phytoplankton species and their interspecific association,the dominance index was calculated,and a comprehensive analysis was conducted including niche width,niche overlap value,ecological response rate,overall association,chi-square test,and the *** phytoplankton community exhibited characteristics of a Cyanobacteria-Chlorophyta-Diatom type community,showing higher diversity in spring and lower diversity in *** 11 dominants phytoplankton species from 3 phyla,both frequency and dominance degree varied seasonally,of which Microcystis *** the dominant species in Spring,Autumn,and *** niche widths of the dominant species ranged from 0.234 to 0.933,and were categorized into three *** niche overlap values of the 11 dominant species ranged from 0.359 to 0.959,exhibiting significant seasonal differences-highest in winter followed by autumn,spring,and summer in *** overall correlation among dominant species in all four seasons revealed a non-significant negative association,resulting in an unstable community structure.A significant portion(84.2%)of species pairs displayed positive associations,suggesting a successional pattern where Diatoms dominated while other dominant species shared resources and *** this pattern,stability measurements indicated that the dominant species community remained unstable.T

关键词： phytoplankton dominant species niche interspecific association Feiyun River basin

生态林场生态保护补偿机制探讨——以山东省东营市为例

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安徽农业科学 2024年第13期52卷 85-87,110页

作者：朱岩芳朱梦洵乔来秋孙燕燕徐丽何洪兵张俊于晓丹王爽东营市湿地保护中心山东东营257091 中咨集团生态技术研究所(北京)有限公司北京100037 山东省黄河三角洲国家级自然保护区管委会山东东营257091

生态林在提高森林覆盖率,调节生态功能,改善人居环境,满足人民群众生态需要等方面发挥着重要作用。推进生态林场建设对维护生态平衡,协调区域高质量发展和高水平保护具有现实意义。为了提升生态林场建设质量和保障生态林场的可持续发展... 详细信息

生态林在提高森林覆盖率,调节生态功能,改善人居环境,满足人民群众生态需要等方面发挥着重要作用。推进生态林场建设对维护生态平衡,协调区域高质量发展和高水平保护具有现实意义。为了提升生态林场建设质量和保障生态林场的可持续发展,需要政府主导,各方参与,完善生态保护补偿政策和机制。以山东省东营市为例,结合座谈访谈、问卷调研、实地考察等方式进行梳理探讨,分析了立地条件相对较差地区生态林场生态保护补偿机制建设存在的问题,并对当前存在的问题提出对策建议,以期推动东营市生态林场的生态保护和可持续经营,为健全完善生态保护补偿机制提供参考依据。

关键词：生态林场生态补偿补偿机制森林管护

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原发性骨质疏松症的诊断和防治

中华内分泌代谢杂志 2006年第3期22卷 205-208页

作者：孟迅吾中国医学科学院北京协和医院内分泌科 100730

骨质疏松症是以骨强度降低、骨折危险性增加为主要表现的骨骼疾病,骨强度反映了骨密度和骨质量的完整性。本文简要介绍现今对原发性骨质疏松症的诊断和防治。诊断基于双能X线吸收法测定的、由世界卫生组织制定标准的骨密度值。预防应置... 详细信息

骨质疏松症是以骨强度降低、骨折危险性增加为主要表现的骨骼疾病,骨强度反映了骨密度和骨质量的完整性。本文简要介绍现今对原发性骨质疏松症的诊断和防治。诊断基于双能X线吸收法测定的、由世界卫生组织制定标准的骨密度值。预防应置于首位,重视对医师和群众的宣教,针对认识上存在的误区。干预的阈值还存在不同的意见,尚须进一步探讨。药物治疗已有不少进展,选择用药应根据本病的特点、循证医学的证据、降低骨折发生和成本及效益分析而进行全面衡量,作出决策。

关键词：骨质疏松骨密度危险因素干预阈值诊断治疗

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原发性骨质疏松症

中华内分泌代谢杂志 1992年第1期8卷 48-50页

作者：孟迅吾北京协和医院内分泌科 100730

原发性骨质疏松症包括绝经后骨质疏松和老年性骨质疏松症。骨质疏松是指单位体积骨量(bone mass)减少为特征的代谢性骨改变,其矿物质和骨基质的比例正常。50岁以上的人几乎都有骨量减少,老年人和绝经后妇女全身骨量减少加速、骨脆性增加... 详细信息

原发性骨质疏松症包括绝经后骨质疏松和老年性骨质疏松症。骨质疏松是指单位体积骨量(bone mass)减少为特征的代谢性骨改变,其矿物质和骨基质的比例正常。50岁以上的人几乎都有骨量减少,老年人和绝经后妇女全身骨量减少加速、骨脆性增加,在轻微外伤或无外伤的情况下均容易发生骨折,尤其70岁以上的老人骨折发生率高。

关键词：原发性骨质疏松

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基于动力特性的南海浮式风力机多准则评价

太阳能学报 2016年第8期37卷 2062-2067页

作者：孟珣田会元李鑫中国海洋大学工程学院山东省海洋工程重点实验室青岛266100 帝恩博国际有限公司中国香港洛克道301-307

基于海上大功率风力机动力特性约束和海洋环境激励要素特征,采用理想最优多准则评估方法,综合考虑海上施工、安装、运营的环境影响、经济性能和结构水动力特性,比较评价南海环境条件下,3种不同大功率浮式风力机——Barge、Spar和TLP的... 详细信息

基于海上大功率风力机动力特性约束和海洋环境激励要素特征,采用理想最优多准则评估方法,综合考虑海上施工、安装、运营的环境影响、经济性能和结构水动力特性,比较评价南海环境条件下,3种不同大功率浮式风力机——Barge、Spar和TLP的整体工作性能。研究结果表明:浮式Spar风力机为给定条件下的理想最优。该方法可用于南海风力发电深水开发结构选型和新型结构开发的综合评价及方案决策。

关键词：海上浮式风力机动力特性 Barge Spar TLP 多准则评价优劣解距离法

Co-doped Ni_(3)S_(2) nanosheet array: A high-efficiency electrocatalyst for alkaline seawater oxidation

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Nano Research 2024年第3期17卷 1050-1055页

作者： meng Yue xun He Shengjun Sun Yuntong Sun Mohamed S.Hamdy Mhamed Benaissa Alsamani A.M.Salih Jun Liu Xuping Sun College of Chemistry Chemical Engineering and Materials ScienceShandong Normal UniversityJinan 250014China Institute of Fundamental and Frontier Sciences University of Electronic Science and Technology of ChinaChengdu 610054China Department of Chemistry College of ScienceKing Khalid UniversityP.O.Box 9004Abha 61413Saudi Arabia Department of Chemical Engineering College of EngineeringUniversity of Ha’ilP.O.Box 2440Ha’il 81441Saudi Arabia Department of Otolaryngology-Head&Neck Surgery West China HospitalSichuan UniversityChengdu 610041China

Developing efficient and durable oxygen evolution reaction(OER)catalysts holds great promise for green hydrogen production via seawater electrolysis,but remains a ***,we report a Co-doped Ni_(3)S_(2) nanosheet array on Ni foam(Co-Ni_(3)S_(2)/NF)as a high-efficiency OER electrocatalyst for *** alkaline conditions,Co-Ni_(3)S_(2)/NF requires an overpotential of only 368 mV to drive 100 mA·cm^(–2),superior to Ni_(3)S_(2)/NF(385 mV).Besides,it exhibits at least 50-h continuous electrolysis.

关键词： Co doping Ni_(3)S_(2)nanosheet array oxygen evolution reaction seawater electrolysis electrocatalyst

Enhanced service stability and thermoelectric performance in Cu_(2)−δSebased composites

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Science China Materials 2024年第7期67卷 2369-2370页

作者： Pengfei Qiu xun Shi State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 200050China

Thermoelectric(TE)materials can directly convert the industrial waste heat into useful electricity based on the Seebeck effect,providing a promising way to tackle the environmental pollution and global energy crisis[1].In the past several decades,many new high-performance TE materials have been discovered to enrich the TE *** them,Cu_(2)−δSe-based TE materials,which are in line with the“phonon-liquid electron-crystal”concept,have sparked widespread interest due to the high TE figure-of-merit(ZT)and the combination of elements that are nontoxic and earth-abundant[2].In 2012,Liu et al.[3]reported a ZT of 1.5 at 1000 K in the stoichiometric Cu_(2)*** alloying S at the Se-site,the ZT was enhanced to around 2.0 at 1000 K[4].Via incorporating carbon nanotubes,the ZT was further enhanced to 2.4 at 1000 K[5].Moreover,Yang et al.[6]and Zhou et al.[7]reported that the ZT of Cu_(2)Se/BiCuSeO composites can reach 2.7–2.8 around 1000 K.

关键词： composites BiCuSeO performance

Research Progress on Bio‑inspired Flapping‑Wing Rotor Micro Aerial Vehicle Development

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Journal of Bionic Engineering 2024年第4期21卷 1621-1643页

作者： Yingjun Pan Shijun Guo xun Huang Centre for Aeronautics School of AerospaceTransport and ManufacturingCranfield UniversityBedford MK430ALUK

Flapping-wing rotor(FWR)is an innovative bio-inspired micro aerial vehicle capable of vertical take-off and *** unique design combines active flapping motion and passive wing rotation around a vertical central shaft to enhance aerodynamic *** research on FWR,though relatively new,has contributed to 6%of core journal publications in the micro aerial vehicle field over the past two *** paper presents the first comprehensive review of FWR,analysing the current state of the art,key advances,challenges,and future research *** review highlights FWR’s distinctive kinematics and aerodynamic superiority compared to traditional flapping wings,fixed wings,and rotary wings,discussing recent breakthroughs in efficient,passive wing pitching and asymmetric stroke amplitude for lift *** experiments and remote-controlled take-off and hovering tests of single and dual-motor FWR models have showcased their *** review compares FWR flight performance with well-developed insect-like flapping-wing micro aerial vehicles as the technology readiness level progresses from laboratory to outdoor flight testing,advancing from the initial flight of a 2.6 g prototype to the current free flight of a 60-gram *** review also presents ongoing research in bionic flexible wing structures,flight stability and control,and transitioning between hovering and cruise flight modes for an FWR,setting the stage for potential applications.

关键词： Flapping-wing rotor Micro aerial vehicle Bio-inspiration Flight

海上大功率风力机固定式支撑结构方案比较分析

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太阳能学报 2018年第11期39卷 3215-3223页

作者：孟珣刘萌唐小惠刘潇涵中国海洋大学工程学院青岛266100 山东省海洋工程重点实验室青岛266100

基于大功率的海上风力机(OWTs)的动力特性约束,优化确定不同水深范围内柔性、刚柔性及刚性设计方案下3种典型固定式海上风电支撑--单立柱、单立柱三桩和导管架式结构主尺度;进一步分析动力特性可行结构方案相应外环境激励及抗力特征不... 详细信息

基于大功率的海上风力机(OWTs)的动力特性约束,优化确定不同水深范围内柔性、刚柔性及刚性设计方案下3种典型固定式海上风电支撑--单立柱、单立柱三桩和导管架式结构主尺度;进一步分析动力特性可行结构方案相应外环境激励及抗力特征不确定分布下结构强度、刚度性能的可靠度指标。研究结果表明:大功率风力机固定式支撑结构水深拓展到100 m,导管架支撑刚柔性设计为经济可行方案,相应方案的单立柱及单立柱三桩存在过大位移及应力。该方法可用于海上风电支撑结构选型和方案决策。

关键词：海上风力机结构优化可靠性分析固有频率单立柱支撑单立柱三桩支撑导管架式支撑