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Chinese Chemical Letters 2012年第7期23卷 859-862页

作者： li chun xuan Qing Jiang Pan School of Chemistry and Materials Science Heilongjiang UniversityHarbin 150080China

One novel organic-inorganic hybrid materials with 4,4＇-bipy ligands and copper chlorine coordination polymers as linkers,with new topology,{[Cu^I（4,4＇-bipy）]_（10）Cl_2（SiW_（12）O_（40））_2}·6H_2O（1）（4,4＇-bipy = 4,4＇-bipyridine）,has been hydrothermally synthesized. The single crystal X-ray structural analysis reveals that the structure of 1 is constructed from classical Keggin anions and[Cu^I（4,4＇- bipy）]cations into a novel,three-dimensional（3D） polyoxometalates（POMs）based *** the topological view,compound 1 is a novel（3.4^4.5^2.6^3）（3^2.4^4.5^6.6^9） *** electrochemical and photocatalysis properties of 1 have been investigated in details.

关键词： Polyoxometalate Tungstoferrate Framework Novel topology

Emerging progress:photochemical transformation of nitroso compounds

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Science China Chemistry 2025年第1期68卷 118-133页

作者： Ze-Le Chen Qiang-Qiang li Armido Studer Jun xuan Anhui Province Key Laboratory of Chemistry for Inorganic/Organic Hybrid Functionalized Materials School of Chemistry&Chemical EngineeringAnhui UniversityHefei 230601China Organisch-Chemisches Institut Universitat MünsterMunster 48149Germany

Nitroso compounds have emerged as highly valuable reaction partners or reagents in organic synthesis due to their rich *** versatile profile of these compounds allows them to function as electrophiles,nucleophiles,diradicals,and radical acceptors in diverse *** recent years,notable progress has been made in harnessing photochemical reactions with nitroso compounds to prepare N,O-containing structures using mild and eco-friendly *** nitroso compounds like nitrosoarenes,acyloxy nitroso compounds,N-nitrosoamines and nitrites have received significant attention for their ability to introduce NO moieties into complex molecules that are otherwise difficult to *** this review,we provide an overview of the recent advancements in the visible light-induced conversion of nitroso compounds,with particular emphasis on their role as bifunctional reagents and acceptors of radicals,carbenes and nitrenes.

关键词： nitroso compounds photochemistry radical reaction carbene transformation nitrosoarenes

Wafer‑Scale Vertical 1D GaN Nanorods/2D MoS_(2)/PEDOT:PSS for Piezophototronic Effect‑Enhanced Self‑Powered Flexible Photodetectors

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Nano-Micro Letters 2025年第3期17卷 102-116页

作者： Xin Tang Hongsheng Jiang Zhengliang lin xuan Wang Wenliang Wang Guoqiang li State Key Laboratory of Luminescent Materials and Devices South China University of TechnologyGuangzhou 510640People’s Republic of China Department of Electronic Materials School of Materials Science and EngineeringSouth China University of TechnologyGuangzhou 510640People’s Republic of China

van der Waals(vdW)heterostructures constructed by lowdimensional(0D,1D,and 2D)materials are emerging as one of the most appealing systems in next-generation flexible ***,hand-stacked vdW-type photodetectors are not compatible with large-areaarray fabrication and show unimpressive performance in self-powered ***,vertical 1D GaN nanorods arrays(NRAs)/2D MoS_(2)/PEDOT:PSS in wafer scale have been proposed for self-powered flexible photodetectors arrays *** as-integrated device without external bias under weak UV illumination exhibits a competitive responsivity of 1.47 A W^(−1)and a high detectivity of 1.2×10^(11)Jones,as well as a fast response speed of 54/71μs,thanks to the strong light absorption of GaN NRAs and the efficient photogenerated carrier separation in type-II ***,the strain-tunable photodetection performances of device have been ***,the device at−0.78%strain and zero bias reveals a significantly enhanced photoresponse with a responsivity of 2.47 A W^(−1),a detectivity of 2.6×10^(11)Jones,and response times of 40/45μs,which are superior to the state-of-the-art self-powered flexible *** work presents a valuable avenue to prepare tunable vdWs heterostructures for self-powered flexible photodetection,which performs well in flexible sensors.

关键词： Vertical nanorod arrays van der Waals heterostructure Piezophototronic effect Self-powered photodetection Flexible sensors

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离解反应速率常数中的方位因素

北京航空航天大学学报 2000年第4期26卷 416-419页

作者：张劲柏李椿萱北京航空航天大学飞行器设计与应用力学系

以碰撞理论为基础探讨了结构方位因素对离解反应速率常数的影响 ,建立了计及方位特征的离解反应模型 ,计算对比了热平衡假设下空气中几个典型的离解反应的Arrhenius图 .结果表明 ,在所选实例中 ,除了反应N2 +N和O2 +O外 ,考虑方位因素... 详细信息

以碰撞理论为基础探讨了结构方位因素对离解反应速率常数的影响 ,建立了计及方位特征的离解反应模型 ,计算对比了热平衡假设下空气中几个典型的离解反应的Arrhenius图 .结果表明 ,在所选实例中 ,除了反应N2 +N和O2 +O外 ,考虑方位因素后确实能够更好地理论估算出反应速率常数 .

关键词：反应动力学化学反应离解反应速率方位因子

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乘波飞行器气动力、热特性的数值模拟研究

宇航学报 2008年第6期29卷 1782-1785页

作者：曹德一李椿萱北京航空航天大学航空科学与工程学院北京100083

采用多块分区网格以及并行计算技术对给定乘波构形的高超声速飞行器进行了数值模拟,分析了飞行器前缘小半径钝化对飞行器气动性能的影响,计算了前缘钝化后飞行器表面的热流分布状况。结果表明,前缘钝化对飞行器的升力影响不大,对阻力和... 详细信息

采用多块分区网格以及并行计算技术对给定乘波构形的高超声速飞行器进行了数值模拟,分析了飞行器前缘小半径钝化对飞行器气动性能的影响,计算了前缘钝化后飞行器表面的热流分布状况。结果表明,前缘钝化对飞行器的升力影响不大,对阻力和升阻比的影响较大。对于曲率半径为1cm的钝化前缘,与原尖前缘飞行器相比,其升力降低了0.78%,阻力增加6.96%,升阻比下降7.21%。前缘钝化后,乘波飞行器仍具有较好的气动性能,飞行器前机身可为发动机提供比较均匀的气流,飞行器整体仍基本保持了乘波的状态,热流主要集中在飞行器前缘上。为了有效防热,需要采用主动式冷却技术。

关键词：乘波飞行器并行计算高超声速数值模拟

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非平衡状态下双原子分子振动态的分布

北京航空航天大学学报 2001年第3期27卷 317-320页

作者：张劲柏李椿萱北京航空航天大学飞行器设计与应用力学系

为尝试修正Hammerling假设 ,在仔细分析了非平衡状态下双原子分子振动态的分布特征的基础上 ,提出了新的分布近似函数 .该近似分布函数能很好地体现非平衡状态下双原子分子振动态分布的主要特征 ,其在离解反应速率的理论计算中的应用也... 详细信息

为尝试修正Hammerling假设 ,在仔细分析了非平衡状态下双原子分子振动态的分布特征的基础上 ,提出了新的分布近似函数 .该近似分布函数能很好地体现非平衡状态下双原子分子振动态分布的主要特征 ,其在离解反应速率的理论计算中的应用也证明是成功的 .

关键词：分布函数化学反应非平衡状态双原子分子振动态飞行器

Enhancing the photocatalytic efficiency by the molecular modification effect derived from pollutant adsorption on highly crystalline BiOBr

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Journal of Environmental Sciences 2025年第2期148卷 263-273页

作者： Yang Jin Tongyin liu Yanpeng Mao Fan li chun Hu National Engineering Laboratory for Reducing Emissions from Coal Combustion Engineering Research Center of Environmental Thermal Technology of Ministry of EducationShandong Key Laboratory of Energy Carbon Reduction and Resource UtilizationSchool of Energy and Power EngineeringShandong UniversityJinan 250061China Beijing Enterprises Water GroupInvestment limited Beijing 100102China Institute of Environmental Research at Greater Bay Key Laboratory for Water Quality and Conservation of the Pearl River DeltaMinistry of EducationGuangzhou UniversityGuangzhou 510006China Key Laboratory of Drinking Water Science and Technology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China

The adsorption of pollutants can not only promote the direct surface reaction,but also modify the catalyst itself to improve its photoelectric characteristics,which is rarely studied for water treatment with inorganic photocatalyst.A highly crystalline BiOBr(c-BiOBr)was synthesized by a two-step preparation *** to the calcination,the highly crystalline enhanced the interface interaction between pollutant and *** complex of organic pollutant and[Bi_(2)O_(2)]^(2+)could promote the active electron transfer from the adsorbed pollutant to c-BiOBr for the direct pollutant degradation by holes(h^(+)).Moreover,the pollutant adsorption actually modified c-BiOBr and promoted more unpaired electrons,which would coupling with the photoexcitation to promote generate more O_(2)^(•-).The molecular modification effect derived from pollutant adsorption significantly improved the removal of *** work strongly deepens the understanding of the molecularmodification effect from the pollutant adsorption and develops a novel and efficient approach for water treatment.

关键词： Highly crystalline BiOBr Pollutant adsorption Molecular modification Photocatalysis Water treatment

Cell polarization in ischemic stroke: molecular mechanisms and advances

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Neural Regeneration Research 2025年第3期20卷 632-645页

作者： Yuanwei li Xiaoxiao Xu xuan Wu Jiarui li Shiling Chen Danyang Chen Gaigai li Zhouping Tang Department of Neurology Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhanHubei ProvinceChina

Ischemic stroke is a cerebrovascular disease associated with high mortality and disability rates. Since the inflammation and immune response play a central role in driving ischemic damage, it becomes essential to modulate excessive inflammatory reactions to promote cell survival and facilitate tissue repair around the injury site. Various cell types are involved in the inflammatory response, including microglia, astrocytes, and neutrophils, each exhibiting distinct phenotypic profiles upon stimulation. They display either proinflammatory or anti-inflammatory states, a phenomenon known as ‘cell polarization.’ There are two cell polarization therapy strategies. The first involves inducing cells into a neuroprotective phenotype in vitro, then reintroducing them autologously. The second approach utilizes small molecular substances to directly affect cells in vivo. In this review, we elucidate the polarization dynamics of the three reactive cell populations(microglia, astrocytes, and neutrophils) in the context of ischemic stroke, and provide a comprehensive summary of the molecular mechanisms involved in their phenotypic switching. By unraveling the complexity of cell polarization, we hope to offer insights for future research on neuroinflammation and novel therapeutic strategies for ischemic stroke.

关键词： astrocyte polarization immune regulation inflammation ischemic injury microglia polarization neutrophil polarization signaling pathways stroke

Characteristics and phytotoxicity of hydrochar-derived dissolved organic matter:Effects of feedstock type and hydrothermal temperature

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Journal of Environmental Sciences 2025年第3期149卷 139-148页

作者： Qianqian Lang xuan Guo Chao Wang lingyao li Yufei li Junxiang Xu Xiang Zhao Jijin li Bensheng liu Qinping Sun Guoyuan Zou Institute of Plant Nutrition and Resources Beijing Academy of Agriculture and Forestry SciencesBeijing 100097China

The dissolved organic matter(DOM)with high mobility and reactivity plays a crucial role in *** this study,the characteristics and phytotoxicity ofDOMreleased fromthe hydrochars prepared from different feedstocks(cowmanure,corn stalk and Myriophyllum aquaticum)under three hydrothermal carbonization(HTC)temperatures(180,200 and 220°C)were *** results showed that the hydrochars had high dissolved organic carbon content(20.15 to 37.65 mg/g)and its content showed a gradual reduction as HTC temperature *** fluorescent components including mixed substance of fulvic acid-like and humic acid-like substances(C1,30.92%-58.32%),UVA humic acid-like substance(C2,25.27%-29.94%)and protein-like substance(C3,11.74%-41.92%)were identified in hydrochar DOM by excitation emission matrix spectra coupled with parallel factor *** HTC temperature increased the relative proportion of aromatic substances(C1+C2)and humification degree of hydrochar DOM from cow manure,while it presented adverse effects on the hydrochar DOM from corn stalk and *** principal component analysis suggested that feedstock type and HTC temperature posed significant effects on the characteristics of hydrochar ***,seed germination test of all hydrochar DOM demonstrated that the root length was reduced by 8.88%-26.43%in contrast with control,and the germination index values were 73.57%-91.12%.These findings provided new insights into the potential environmental effects for hydrochar application in soil.

关键词： Hydrochar Hydrothermal temperature Dissolved organic matter Excitation emission matrix Parallel factor analysis Phytotoxicity

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高超高焓非平衡流动数值模拟方法研究综述

力学进展 2023年第3期53卷 561-591页

作者：高振勋蒋崇文李椿萱北京航空航天大学航空科学与工程学院北京100191

高性能计算流体力学(computational fluid dynamic,CFD)模拟可以与高超飞行试验、高焓地面设备实验研究相互印证,在热化学非平衡效应研究以及未来高超声速飞行器研制中将发挥更重要的作用.本文回顾了国内外在热化学非平衡流动CFD研究方... 详细信息

高性能计算流体力学(computational fluid dynamic,CFD)模拟可以与高超飞行试验、高焓地面设备实验研究相互印证,在热化学非平衡效应研究以及未来高超声速飞行器研制中将发挥更重要的作用.本文回顾了国内外在热化学非平衡流动CFD研究方面的进展,概述了相关热化学模型、数值格式研究以及CFD软件研制方面的现状和发展趋势,最后指出了今后在基础研究、软件开发、模拟应用等方面需要关注的问题.(1)在热化学模型方面,常用温度模型并不完全精确,多振动温度模型具有发展潜力但工程应用受限,态−态模型更精确但模拟技术尚不成熟,更为精确的热力学输运模型、有限速率化学反应模型、振动−离解耦合模型以及表面效应模型等是提升热化学非平衡模拟精度的重要物理模型,值得深入研究;(2)在数值方法方面,多物理场耦合模拟是高超热化学非平衡流动CFD研究的热点和趋势,对CFD方法的鲁棒性和收敛性提出了更高的要求,值得重点关注和研究,此外常用数值格式需要针对热化学非平衡流动特征进行适应性改造,RANS方法在热化学非平衡湍流模拟中的计算可靠性仍有待验证;(3)在数值软件方面,基于结构/非结构混合网格的数值求解器更加符合工业应用需求,未来高超数值软件需要具备稳定、鲁棒的多学科、多物理场耦合求解功能,且能够适应更大网格规模大尺度复杂外形的模拟需求;(4)可综合应用多种加速技术手段提升热化学非平衡流动数值模拟的计算效率,计算刚性是热化学非平衡流动数值模拟方法研究的共性基础问题,刚性消除方法仍需进一步研究和发展.

关键词：高超声速热化学非平衡高焓计算流体力学(CFD) 计算刚性