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Cladophora as ecological engineer:A new test from the largest lake of Qinghai-Tibet plateau with filamentous algal blooms

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Water Biology and Security 2024年第1期3卷 46-52页

作者： Zhihua Wu Xigong Yuan Xiong Xiong Hongyi ao Chenxi Wu Guoxiang Liu Huan Zhu Institute of Hydrobiology Chinese Academy of SciencesWuhan430072China College of Science Tibet UniversityLhasa850001China Huaihe River Commission of the Ministry of Water Resources Bengbu233001China

Filamentous algae blooms(FABs)have been increasing globally in recent years,and their presence can have both harmful and beneficial effects on aquatic *** one of the most common FABs,Cladophora blooms have been reported in the lakes of the Qinghai-Tibet Plateau during the past few ***,there have been few studies focused on how FABs impact other aquatic organisms,especially in alpine lakes since these are at the forefront of responding to global climate *** this study,the phytoplankton communities in different regions of Qinghai Lake were profiled in different seasons using meta-barcode *** phytoplankton assemblages in areas with Cladophora blooms were compared to those without *** phytoplankton community structure correlated with physicochemical properties including water temperature,electrical conductivity,nitrate,and the presence or absence of Cladophora *** relative abundance of Bacillariophytes was found to be higher in zones with Cladophora blooms than in other *** seasonal changes in phytoplankton biomass andβdiversity were observed in zones with Cladophora *** and microbial degradation of Cladophora can change the pH,dissolved oxygen,secchi depth,and *** with seasonal temperature and electrical conductivity changes,Cladophora growth can significantly impact the phytoplankton biomass,community dissimilarity and assembly *** results showed that Cladophora plays a key role in littoral aquatic ecosystem ecology.

关键词： Filamentous algal blooms Qinghai lake Biodiversity Phytoplankton community Assembly processes Environmental drivers

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非对称升力翼对高速列车横风气动性能的影响

中南大学学报（自然科学版） 2024年第5期55卷 1678-1690页

作者：李志榕王哲许澳张洁中南大学建筑与艺术学院湖南长沙410083 中南大学交通运输工程学院轨道交通安全教育部重点实验室湖南长沙410075 中南大学重载快捷大功率电力机车全国重点实验室湖南长沙410075 中南大学轨道交通列车安全保障技术国家地方联合工程研究中心湖南长沙410075

随着高速列车运行速度的不断提升,横风环境下列车运行安全问题日益凸显。为此,从控制气动升力角度提出一种非对称升力翼结构以期形成抗倾覆力矩,并采用数值模拟方法,对比分析原始车型、全展开升力翼车型和收缩迎风侧升力翼车型的气动载... 详细信息

随着高速列车运行速度的不断提升,横风环境下列车运行安全问题日益凸显。为此,从控制气动升力角度提出一种非对称升力翼结构以期形成抗倾覆力矩,并采用数值模拟方法,对比分析原始车型、全展开升力翼车型和收缩迎风侧升力翼车型的气动载荷及列车周围流场结构,探究横风环境下该结构对列车横风气动性能的影响。研究结果表明:升力翼对高速列车气动载荷及周围流场影响显著;列车安装升力翼后主要改变了车顶和车体背风侧表面压力分布以及车顶、车体背风侧和尾流区域的速度分布;车体顶部由于受到非对称升力翼压力面影响,在升力翼下方车顶区域形成了低速高压区且向车体背风侧延伸;同时,车体背风侧表面压力升高,在升力翼下游车体背风侧空间区域,由流动分离导致的漩涡结构发生了明显改变;相比于原始车型,收缩迎风侧升力翼车型(模型Ⅱ和模型Ⅲ)均可减小列车横向力和倾覆力矩;模型Ⅲ效果最显著,3车编组列车横向力和倾覆力矩分别减少13.19%和11.86%。

关键词：高速列车升力翼非对称布置抗倾覆性能

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Sport medicine among the past three decades in China

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Chinese Medical Journal 2024年第7期137卷 757-761页

作者： Yingfang ao Wenqiang Yan Yue Wu Institute of Sports Medicine of Peking University Beijing 100191China Beijing Key Laboratory of Sports Injuries Beijing 100191China

In 1955,Professor Mianyu Qu,the founder of Chinese sports medicine,and the older generation of sports medicine practitioners,founded China’s sports medicine in response to the needs of the development of national sports and *** therst 30 years of the establishment of sports medicine,they played an important role in the academic development,talent cultivation,international communication,construction of the society and organization,national Olympic glory,and national*** contributions established a solid foundation for the rapid development of China’s sports medicine in the following 30 years.

关键词： sports academic medicine

Spray pyrolysis-derived W-doped MoSe_(2)/rGO paper-like microspheres:optimization of microstructure and mesostructure for enhanced lithium storage

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Rare Metals 2024年第7期43卷 3019-3031页

作者： Wei Wang Jun-Yu Chen Jie Ouyang Hong Yin ao-Jie Li Liang Chen Jun-Lin Huang Yu-Can Zhu Gang-Yong Li Zhao-Hui Hou Key Laboratory of Hunan Province for Advanced Carbon-based Functional Materials Hunan Institute of Science and TechnologyYueyang 414006China School of Chemistry and Chemical Engineering Hunan Institute of Science and TechnologyYueyang414006China Hunan Province Key Laboratory of Materials Surface&Interface Science and Technology Material Science and Engineering SchoolCentral South University of Forestry and TechnologyChangsha 410004China International Iberian Nanotechnology Laboratory(INL) AvMestre Jose Veiga4715-330 BragaPortuga

Two-dimensional MoSe_(2) is a promising candidate for lithium-ion battery ***,its conductivity and lithium storage volumetric effect still need to be *** this work,W-doped MoSe_(2)/rGO paper-like microspheres are successfully prepared through ultrasonic spray pyrolysis,achieving optimization at both the microstructure and mesostructure to enhance the lithium storage performance of the ***,by utilizing the similar two-dimensional structure between MoSe_(2) and rGO,self-assembly is achieved through spray pyrolysis,resulting in a well-defined van der Waals heterostructure at the interface on the microscale,enhancing the electron and ion transfer capability of the ***,the mesoscale paper-like microsphere morphology provides additional volume expansion buffering ***,W-doping not only increases the interlayer spacing of MoSe_(2)(0.73 nm),thereby reducing the diffusion resistance of Li+,but also allow for the modulation of the energy band structure of the *** functional theory(DFT)calculations confirm that W-doped MoSe_(2)/rGO exhibits the narrowest bandgap(0.892 eV).Therefore,the composite demonstrates excellent lithium storage performance,maintaining a specific capacity of 732.9 mAh·g^(-1)after 300 cycles at a current density of 1 A·g^(-1).

关键词： Molybdenum selenide Heterostructure Microspheres Li-ion batteries Kinetics

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低增益雪崩探测器的数值仿真与辐照效应研究

辐射防护 2024年第3期44卷 265-274页

作者：张翔铭孙世峰张翱华北电力大学核科学与工程学院北京102206

低增益雪崩探测器(LGAD)是新型快速定时探测器,用于克服在重强子辐射下传统硅探测器响应速度慢和抗辐照能力差的问题。使用计算机辅助设计工具(TCAD),构建LGAD的物理模型,对不同温度、电压下LGAD的漏电流、瞬态信号和增益等的变化进行... 详细信息

低增益雪崩探测器(LGAD)是新型快速定时探测器,用于克服在重强子辐射下传统硅探测器响应速度慢和抗辐照能力差的问题。使用计算机辅助设计工具(TCAD),构建LGAD的物理模型,对不同温度、电压下LGAD的漏电流、瞬态信号和增益等的变化进行研究。引入一种新的“三陷阱体损伤模型”研究LGAD的抗辐照性能,计算不同中子辐照通量对LGAD相关电学参数的影响。结果表明:LGAD在低温下工作具有更好的性能;辐照后漏电流增大,暗计数率增加,瞬态收集信号变差,增益降低。分析认为是辐照所产生的缺陷影响了LGAD的空间有效电荷和内部电场,通过增大电压和降低温度可以降低这一影响。模拟研究工作得到了不同温度和辐照对探测器性能的影响,对探测器后续的研究和辐照加固设计具有指导意义。

关键词：低增益雪崩探测器 TCAD仿真中子辐照辐照模型

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Advocating for the implementation of SonoVue microbubbles as pressure sensors: a call to action for clinical noninvasive pressure estimation

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Hepatobiliary Surgery and Nutrition 2024年第4期13卷 690-695页

作者： ao Wen Lingxiao Yang Tao Lv Huayu Yang Fei Li Yilei Mao Gang Xu Jia-Yin Yang Liver Transplant Center Organ Transplant CenterWest China Hospital of Sichuan UniversityChengduChina Laboratory of Liver Transplantation Key Laboratory of Transplant Engineering and ImmunologyNational Health Commission(NHC)West China Hospital of Sichuan UniversityChengduChina West China Hospital West China School of MedicineSichuan UniversityChengduChina Department of Liver Surgery Peking Union Medical College(PUMC)HospitalPUMC and Chinese Academy of Medical SciencesBeijingChina Paul C.Lauterbur Research Center for Biomedical Imaging Shenzhen Institutes of Advanced TechnologyChinese Academy of SciencesShenzhenChina

Pressure measurement within the body is of pivotal significance in the diagnosis of vascular and organ-related diseases associated with hydrostatic *** present,the most commonly used clinical method is to insert a catheter along with a pressure sensor and then guide it to the area of interest through vessels such as central venous pressure(CVP).However,the presence of sensors within the vessel of interest will inevitably cause alterations to the circulation and thus affect blood ***,the use of invasive methods does not allow monitoring of every area inside the body.

关键词： SonoVue microbubbles pressure estimation noninvasive

基层治理示范效应的生成与异化研究——以A市X社区的旧改典型示范项目建设为例

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公共管理学报 2024年第3期21卷 137-151,175页

作者：崔子傲张平东北大学文法学院沈阳110169

典型示范作为中国情境中的一种政策执行工具,在治理实践中发挥着举足轻重的作用。通过对A市老旧小区改造过程中X社区典型示范创建的过程分析,发现典型示范创建不仅仅是一种政策工具应用,也是一种深入的政治和社会互动过程,有其独特的运... 详细信息

典型示范作为中国情境中的一种政策执行工具,在治理实践中发挥着举足轻重的作用。通过对A市老旧小区改造过程中X社区典型示范创建的过程分析,发现典型示范创建不仅仅是一种政策工具应用,也是一种深入的政治和社会互动过程,有其独特的运作逻辑和作用机制。本文将典型示范的运作逻辑理解为多行动主体按照情境规则形成的组织模式变化过程,涉及多方的塑造动力和相互作用。在典型示范建设的动态过程中,随着任务情境流转,基层治理中的行动主体面临内外要素不同组合驱动,卷入典型示范创建竞赛,并产生了相应的行动逻辑。研究发现:通过阶段性建设累积和集成式资源配置,助推形成了“以点带面”的典型示范效应,基于科层制度下的官僚主义主导着政社间的互动关系,决定了创建行动者之间的角色位序,酝酿着典型示范创建目标替代及效应异化的风险,必须防范其对正向效能及治理总体绩效的侵蚀。

关键词：典型示范创建内外驱动行为逻辑异化风险基层治理

Selective Alkane Desaturation Catalyzed by Molecular Cage Copper Complexes Under Mild Conditions

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CCS Chemistry 2024年第8期6卷 1876-1884页

作者： Hao Sun Xue-Yuan Wang Xu-Dong Wang Yu-Fei ao De-Xian Wang Qi-Qiang Wang Beijing National Laboratory for Molecular Sciences CAS Key Laboratory of Molecular Recognition and FunctionInstitute of ChemistryChinese Academy of SciencesBeijing 100190 University of Chinese Academy of Sciences Beijing 100049

Catalytic oxidative alkane desaturation by base metals with benign oxidants under mild conditions is highly attractive,as it could enable an efficient way to produce valuable olefin *** we report the design and synthesis of macrocyclic and molecular cage copper complexes in catalyzing highly selective cyclohexane desaturation with H_(2)O_(2)/O_(2).The macrocycles and cages possess two to three phenanthroline units connected by versatile binary linkers or tripodal *** compounds readily formed bi-and tri-nuclear copper complexes with confined cavities and adaptive coordination environments,as suggested by X-ray single crystal *** the catalytic oxidation of cyclohexane,a considerable yield of cyclohexene with unprecedented dehydrogenation/oxygenation selectivity up to 6.1:1 was achieved with the optimal cage compound *** and mechanistic experiments suggested a pronounced cage effect and radical-mediated *** high selectivity was attributed to a cooperative effect between the copper centers,which facilitated the second hydrogen atom abstraction on the trapped cyclohexyl radical and the inhibition of the Fenton process within the shielding cavity environment.

关键词： supramolecular catalysis macrocycles molecular cages phenanthroline alkane desaturation

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基层治理场域中城市社区政策执行逻辑解构

学习与实践 2024年第1期 42-51页

作者：张平崔子傲东北大学文法学院辽宁沈阳110169

城市社区是基层治理基本单元,也是回应社会治理问题的主战场。相较于科层治理模式,基层治理场域建构起了独特的治理格局,在此场域中城市社区政策执行具有特殊的情境逻辑。基于场域-行为的社区政策执行场域分析框架,对执行主体进行角色... 详细信息

城市社区是基层治理基本单元,也是回应社会治理问题的主战场。相较于科层治理模式,基层治理场域建构起了独特的治理格局,在此场域中城市社区政策执行具有特殊的情境逻辑。基于场域-行为的社区政策执行场域分析框架,对执行主体进行角色行为分析,可以发现,社区治理情境中的压力型体制背景、政策设计内生性模糊与组织资本困窘、场域叠加、行动者区隔,以及政策执行者心理系统等场域要素,共同作用于政策执行行为。从组织场域、社会关系场域以及心理场域对城市社区的政策执行进行全方位及全过程调节,将极大地提升社会治理政策效能。

关键词：基层治理场域理论政策执行行为逻辑