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Ambient Particulate Matter Pollution and Hospital Visits for Cardiac Arrhythmia in Beijing,China

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Biomedical and Environmental Sciences 2021年第7期34卷 562-566页

作者： WU Jun Hui WU Yao wang Zi Jing TIAN Yao Hua WU Yi Qun WU Tao wang Meng Ying wang Xiao Wen wang jia ting HU Yong Hua Department of Epidemiology and Biostatistics School of Public HealthPeking UniversityBeijing 100191China Medical Informatics Center Peking UniversityBeijing 100191China

Cardiac arrhythmia is a serious public health problem in many *** studies estimated that 33.5 million people are affected by cardiac arrhythmia worldwide,and this number will continue to grow as society *** improvements in diagnostic and therapeutic interventions in electrophysiology,the disease burden,incidence and prevalence of cardiac arrhythmia continue to increase and have aroused public health *** evidence has indicated that air pollution may be associated with cardiac autonomic nervous *** air pollutants,particulate matter with an aerodynamic diameter of≤2.5μm(PM_(2.5))is considered exert more toxicity than other air pollutants,as it provides a larger surface area and absorbs or condenses more toxic substances per unit mass.

关键词： Cardiac arrhythmia cardiac

Molecular-based porous polymers with precise sites for photoreduction of carbon dioxide

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Chinese Chemical Letters 2025年第1期36卷 201-213页

作者： Wei-jia wang Kaihong Chen College of Biological and Chemical Engineering Zhejiang University of Science and TechnologyHangzhou 310023China The Institute of Green Chemistry and Engineering School of Chemistry and Chemical EngineeringNanjing UniversitySuzhou 215163China

Photocatalytic CO_(2)reduction reaction(CO_(2)RR)is one of the promising strategies for sustainably producing solar *** precise identification of catalytic sites and the enhancement of photocatalytic CO_(2)conversion is imperative yet quite *** critical review summarizes recent advances in porous photo-responsive polymers,including covalent organic frameworks(COFs),covalent triazine frameworks(CTFs),and conjugated microporous polymers(CMPs),those can be rationally designed from the molecular level for visible-light-driven photocatalytic CO_(2)***,special emphasis is placed on how the well-defined active sites on these polymers can influence their properties and photocatalytic *** precise regulation and control of microenvironments and electronic properties of metal active centers are crucial for boosting catalytic efficiency and selectivity,as well as for the design of better photocatalysts for CO_(2)reduction.

关键词： Carbon dioxide reduction Photocatalysis Porous polymers Well-defined catalytic sites Molecular level

Experiments and modeling of microstructural and mechanical behaviors of laser-welded Ni-based superalloy at high temperatures

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Chinese Journal of Aeronautics 2025年第1期38卷 99-114页

作者： ting HOU Yong LI Degang wang Yuelin wang Marko VILOTIC School of Mechanical Engineering and Automation Beihang UniversityBeijing 100191China Department of Structure Shenyang Aircraft Designand Research InstituteShenyang 110000China Engineering Center Shenyang Aircraft CorporationShenyang 110000China Faculty of Technical Science University of Novi SadNovi Sad 21102Serbia

The performance of welded Ni-based superalloys at high temperatures is essential to be evaluated due to their particular service environment for aero-engines and high-speed *** tensile properties and related microstructural evolutions such as the carbide precipitate and grain of a laser-welded Ni-based alloy were experimentally and numerically investigated at different temperatures(20,300,500,800℃).The results show that at room temperature,the strength of the Base Material(BM)was slightly smaller,with a difference of less than 1%,than the Welded Material(WM),which can be attributed to the more uniformly distributed needle-shaped carbide precipitates in the WM than those nonuniformly coarser spherical ones in the *** at 300℃ and 500℃,the strength of WM decreased more obviously compared with that of BM due to the more apparent growth of grain:13.52%loss in yield strength in WM alloys as compared with BM alloys at 300℃,and 16.57% at 500℃.At 800℃,the strength of BM and WM both decreased to a similar level due to Dynamic Recrystallization(DRX).However,a much higher elongation was observed for the BM than WM(less than 50%of BM),which can be attributed to the enhanced dislocation accumulation capability of the large spherical carbides along grain boundaries on the fracture surface in ***,a unified model considering the welding effects on both microstructures(dislocation,carbides,and grain)and mechanical properties evolutions at different temperatures was developed and *** on this model,the key temperature ranges(20–600℃)where apparent weakening of strength and uniform plasticity occurs for welded structures were identified,providing a direct guidance for potential structure and process design.

关键词： Ni-based superalloy Microstructure Mechanical properties Constitutive model High temperature

MXene Hybridized Polymer with Enhanced Electromagnetic Energy Harvest for Sensitized Microwave Actuation and Self‑Powered Motion Sensing

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Nano-Micro Letters 2025年第3期17卷 265-279页

作者： Yu‑Ze wang Yu‑Chang wang ting‑ting Liu Quan‑Liang Zhao Chen‑Sha Li Mao‑Sheng Cao School of Materials Science and Engineering Beijing Institute of TechnologyBeijing 100081People’s Republic of China School of Materials Science and Engineering Peking UniversityBeijing 100871People’s Republic of China School of Mechanical and Material Engineering North China University of TechnologyBeijing 100144People’s Republic of China Key Laboratory of Functional Inorganic Material Chemistry Ministry of Education of the People’s Republic of ChinaHeilongjiang UniversityHarbin 150080People’s Republic of China

Polymeric microwave actuators combining tissue-like softness with programmablemicrowave-responsive deformation hold great promise for mobile intelligentdevices and bionic soft robots. However, their application is challenged by restricted electromagneticsensitivity and intricate sensing coupling. In this study, a sensitized polymericmicrowave actuator is fabricated by hybridizing a liquid crystal polymer with Ti3C2Tx(MXene). Compared to the initial counterpart, the hybrid polymer exhibits unique spacechargepolarization and interfacial polarization, resulting in significant improvements of230% in the dielectric loss factor and 830% in the apparent efficiency of electromagneticenergy harvest. The sensitized microwave actuation demonstrates as the shortenedresponse time of nearly 10 s, which is merely 13% of that for the initial shape memory polymer. Moreover, the ultra-low content of MXene (upto 0.15 wt%) benefits for maintaining the actuation potential of the hybrid polymer. An innovative self-powered sensing prototype that combinesdriving and piezoelectric polymers is developed, which generates real-time electric potential feedback (open-circuit potential of ~ 3 mV) duringactuation. The polarization-dominant energy conversion mechanism observed in the MXene-polymer hybrid structure furnishes a new approachfor developing efficient electromagnetic dissipative structures and shows potential for advancing polymeric electromagnetic intelligent devices.

关键词： Microwave absorption Electromagnetic response Energy harvest Self-sensing Soft actuator

Spatiotemporal evolution of wildfire activity during the Paleocene-Eocene Thermal Maximum in China

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Science China Earth Sciences 2025年第2期68卷 509-522页

作者： Xue-ting wang Zuoling CHEN Linlin CUI Xu wang State Key Laboratory of Lithospheric and Environmental Coevolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China University of Chinese Academy of Sciences College of Earth and Planetary SciencesBeijing 100049China Institute of Geology and Geophysics Chinese Academy of SciencesBeijing 100029China

The Paleocene-Eocene Thermal Maximum(PETM)was the most prominent warming event in the Cenozoic and serves as a geological analog for the current global warming driven by anthropogenic CO_(2)emissions from burning fossil *** a primary disruptor of Earth's ecosystems,wildfire activity affects the balance of ecosystems,the global carbon cycle,and climate ***,studying the evolution and driving mechanisms of wildfires during the PETM is essential for predicting wildfire activity under global warming scenarios and for understanding the carbon cycle in the context of wildfire *** research on wildfires during the PETM has mainly focused on the Northern Hemisphere,particularly Europe and North America,whereas studies on Chinese mainland remain *** this study,we analyzed black carbon(BC)concentration and carbon isotope(δ13C)in the Beigou section of the Nanyang Basin and the Xilutian section of the Fushun Basin to reconstruct the spatiotemporal evolution of wildfires in arid/semi-arid and humid *** integrated these findings with those of previous studies on the paleoclimate of the research area to elucidate the driving mechanisms behind wildfire *** results indicate that wildfire activity weakened at the onset of the PETM,with the negative carbon isotope period characterized by low wildfire activity,except for a brief resurgence in the Nanyang *** the recovery phase of the PETM,wildfire activity gradually increased,returning to the pre-PETM *** prolonged low wildfire state was likely caused by extremely high temperatures and precipitation as well as the resulting vegetation *** the PETM recovery phase,increased wildfire activity transformed“short-term carbon sinks”of the biological-atmospheric carbon cycle into“long-term carbon sinks”through the burial of *** process of carbon sink conversion may have acted as a negative feedback mechanism,contributing to carbon sequestration and the e

关键词： PETM Wildfire Carbon cycle Nanyang Basin Fushun Basin

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中国区域经济增长中的土地资源尾效研究

经济地理 2010年第12期30卷 2067-2072,2121页

作者：王家庭南开大学中国城市与区域经济研究中心中国天津300071

依据建立的土地资源尾效测算模型,运用面板数据分析方法,从区域维度和时间维度对我国内地31省区经济增长中的土地资源尾效进行了实证研究,并分析了土地资源尾效存在区域差异的原因。研究发现:①不同地区的土地资源尾效值整体差异较大;... 详细信息

依据建立的土地资源尾效测算模型,运用面板数据分析方法,从区域维度和时间维度对我国内地31省区经济增长中的土地资源尾效进行了实证研究,并分析了土地资源尾效存在区域差异的原因。研究发现:①不同地区的土地资源尾效值整体差异较大;②不同地区的土地资源尾效值随时间变化差异较大;③人口增长率的提升、土地资源的弹性系数较高和资本的弹性系数较高是土地资源尾效存在区域差异的主要原因。

关键词：区域经济增长土地资源尾效

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教育对我国农村经济贡献率的区域比较研究

教育科学 2012年第5期28卷 1-7页

作者：王家庭南开大学中国城市与区域经济研究中心天津300071 教育部-南开大学教育与产业区域发展研究中心天津300071

基于丹尼森算法运用省区面板数据测算了1990-2008年教育对区域农村经济增长的贡献率,并进行区域差异比较。结果发现:(1)区域间教育对经济增长的贡献率存在显著不同,1990-2008年间西部地区教育贡献率最大,东部次之,中部最低;(2)不同区域... 详细信息

基于丹尼森算法运用省区面板数据测算了1990-2008年教育对区域农村经济增长的贡献率,并进行区域差异比较。结果发现:(1)区域间教育对经济增长的贡献率存在显著不同,1990-2008年间西部地区教育贡献率最大,东部次之,中部最低;(2)不同区域教育贡献率的时间变化趋势不同,东部地区2000年-2008年间教育贡献率较之1990-1999年有所降低,而中、西部地区均有较大提升;(3)不同区域起主要贡献作用的教育等级不同,当前阶段东部地区高等教育的贡献率最大,中西部地区则为高中教育。进一步分析发现,北京、海南、辽宁、宁夏、贵州、内蒙谷等少部分省区教育贡献率与所在区域平均情况有明显的差异。在此基础上,提出了具有区域针对性的政策建议。

关键词：教育农村经济贡献率区域

教育对我国区域经济增长的贡献--基于31省区面板数据的实证研究

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复旦教育论坛 2013年第3期11卷 30-36,42页

作者：王家庭南开大学教育与产业、区域发展研究中心天津300071

作者通过利用教育生产函数对我国1996-2009年教育对区域经济增长的贡献进行了实证研究,并进一步运用空间计量方法,计算出Moran指数及其散点图,来分析教育对我国区域经济增长贡献的空间相关性和空间分布特征。研究结果表明:(1)我国教育... 详细信息

作者通过利用教育生产函数对我国1996-2009年教育对区域经济增长的贡献进行了实证研究,并进一步运用空间计量方法,计算出Moran指数及其散点图,来分析教育对我国区域经济增长贡献的空间相关性和空间分布特征。研究结果表明:(1)我国教育对区域经济增长具有明显的促进作用,其中高等教育对区域经济增长的贡献率最大;(2)我国中等教育对区域经济增长的贡献水平及其增长的空间分布不是随机的,而是在全局和局域环节都呈现正向的空间依赖特征,表现为高水平的区域倾向于集聚在一起;(3)初等教育和高等教育对区域经济增长的贡献水平没有出现明显的空间依赖性。

关键词：教育区域经济增长 Moran指数贡献

Biogenic emission as a potential source of atmospheric aromatic hydrocarbons:Insights from a cyanobacterial bloom-occurring eutrophic lake

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Journal of Environmental Sciences 2025年第5期151卷 497-504页

作者： Hua Fang ting Wu Shutan Ma Yuqing Miao Xinming wang School of Ecology and Environment Anhui Normal UniversityWuhu 241000China Center of Cooperative Innovation for Recovery and Reconstruction of Degraded Ecosystem in Wanjiang City Belt Wuhu 241000China School of Geography and Tourism Anhui Normal UniversityWuhu 241000China State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization Guangzhou Institute of GeochemistryChinese Academy of SciencesGuangzhou 510640China CAS Center for Excellence in Deep Earth Science Guangzhou 510640China

As important precursors of ozone(O_(3))and secondary organic aerosol(SOA),reactive aromatic hydrocarbons(AHs)have typically been classified as anthropogenic air ***,biogenic emission can also be a potential source of atmospheric ***,field observations in a eutrophic lake were combined with laboratory incubation experiments to investigate the biogenic AH *** work showed that the water-air fluxes of AHs measured at sites with high cyanobacteria abundance could reach an order of magnitude greater than those at sites with low cyanobacteria abundance,suggesting that cyanobacteria could be the important contributor to measured *** incubation experiments further confirmed the AH emission of cyanobacteria and revealed that the emission could change significantly over the lifespan of cyanobacteria and varied to their growing *** combining field observations and laboratory incubation experiments,it has been suggested that the emission of different AH species from cyanobacteria could be modulated by variable biogeochemical mechanisms and that the biochemical process of toluene could be different from that of other *** study investigates AH emissions from inland aquatic ecosystem and suggests that biogenic emission could be a potential source of atmospheric AHs.

关键词： Aromatic hydrocarbons Biogenic emission Eutrophic lake Cyanobacteria Biosphere-atmosphere exchange