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Rare Metals 2024年第2期43卷 624-634页

作者： Xing-yuan Zhang Mei-Na Lei shan Tian Jian-Gan Wang State Key Laboratory of Solidification Processing Center for Nano Energy MaterialsSchool of Materials Science and EngineeringNorthwestern Polytechnical University and Shaanxi Joint Laboratory of Graphene(NPU)Xi’an710072China

High-energy-density Li-S batteries are subjected to serious sulfur deactivation and short cycle lifetime caused by undesirable polysulfide shuttle effect and frantic lithium dendrite *** this work,a controllable cage-confinement strategy to fabricate molybdenum carbide(MoC)nanoclusters as a high-efficient sulfiphilic and lithiophilic regulator to mitigate the formidable issues of Li-S batteries is *** sub-2 nm MoC nanoclusters not only guarantee robust chemisorption and fast electrocatalytic conversion of polysulfides to enhance the sulfur electrochemistry,but also homogenize Li^(+) flux to suppress the lithium dendrite *** a consequence,the MoC-modified separator endows the batteries with boosted reaction kinetics,promoted sulfur utilization,and improved cycling stability.A reversible capacity of 701 mAh·g^(−1) at a high rate of 5.0C and a small decay rate of 0.076%per cycle at 1.0C over 600 cycles are *** study offers a rational route for design and synthesis of bifunctional nanoclusers with both sulfiphilicity and lithiophilicity for high-performance Li-S batteries.

关键词： Li-S batteries Nanocluster Electrocatalyst Polysulfide shuttle Li dendrites

One-step pore diffusion mechanism of Li^(+) in solid electrolyte interphase for fast-charging lithium-ion battery

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Rare Metals 2024年第7期43卷 3438-3440页

作者： shan Wang Shu-yuan Liu Alireza Khataee Ke-Zhen Qi College of Pharmacy Dali UniversityDali 671000China Research Laboratory of Advanced Water and Wastewater Treatment Processes Department of Applied ChemistryFaculty of ChemistryUniversity of TabrizTabriz 51666-16471Iran Peoples'Friendship University of Russia(RUDN University) Moscow117198Russian Federation

Li^(+) transport in solid electrolyte interphase is recognized as important factor,which has become a research ***,an one-step pore diffusion mechanism for Li^(+) transport through solid electrolyte interphase was proposed,which was different from previous two-step *** one-step pore diffusion process could effectively eliminate the dynamic limitations of Li^(+) transport in solid electrolyte interphase (SEI) for rapid charging *** work will contribute to the development of rapid charging lithium-ion batteries.

关键词： battery mechanism electrolyte

Trace determination of hexabromocyclododecane diastereomers in water samples with temperature controlled ionic liquid dispersive liquid phase microextraction

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Chinese Chemical Letters 2011年第1期22卷 97-100页

作者： Ru Song Zhao Xia Wang Jin Peng yuan shan shan Wang Chuan Ge Cheng Key Laboratory for Applied Technology of Sophisticated Analytical Instruments of shandong Province Analysis and Test Center Shandong Academy of Sciences Jinan 250014 China

A novel temperature controlled ionic liquid dispersive liquid phase microextracfion （TCIL-DLPME） coupled with rapid resolution liquid chromatography-electrospray tandem mass spectrometry （RRLC-ESI-MS-MS） has been developed for the enrichment and determination of three hexabromocyclododecane diastereomers （HBCDs） in water samples. Green solvent ionic liquid （IL） was used as extraction solvent instead of toxic organic solvents. This technique also avoided the usage of dispersive solvent. Some important parameters that might affect the extraction efficiency were optimized. Under the optimum conditions, good linear relationship, sensitivity and reproducibility were obtained. All the limits of detection for the three diastereomers were 0.1 ng/ mL. The linear range was obtained in the range of 1-100 ng/mL for the total amount of three HBCD diastereomers. It was satisfactory to analyze real environmental water samples with the recoveries ranging from 77.2% to 99.3%. The main advantage of the method is toxic organic solvent-free.

关键词： Hexabromocyclododecane Temperature controlled ionic liquid dispersive liquid phase microextraction Rapid resolution liquidchromatography-electrospray tandem mass spectrometry

基于纳秒LIBS的氢气/空气火焰混合分数测量研究

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光谱学与光谱分析 2025年第1期45卷 24-29页

作者：刘子晗刘艳韩磊单沅鲁政高强李帅瑶李博天津大学内燃机燃烧学国家重点实验室天津300072 中国科学院工程热物理研究所北京100190

在双碳政策和化石能源短缺的背景下,氢能作为高效环保的清洁能源,受到广大研究人员的关注。氢气/空气混合燃烧作为推动氢能规模化应用的重要途径,其燃烧机理和关键参数的测量技术成为目前研究的热点。燃空当量比是表征燃烧过程中燃料与... 详细信息

在双碳政策和化石能源短缺的背景下,氢能作为高效环保的清洁能源,受到广大研究人员的关注。氢气/空气混合燃烧作为推动氢能规模化应用的重要途径,其燃烧机理和关键参数的测量技术成为目前研究的热点。燃空当量比是表征燃烧过程中燃料与氧化剂混合程度的重要参数,直接影响燃烧的开始、自持以及燃烧化学反应的活跃程度。因此,对燃烧过程中的局部当量比实时在线监测,对于改善燃烧效率、控制燃烧过程具有重要意义。目前,可以实时测量氢气/空气火焰当量比的方法相对较少,激光光谱技术作为一种非侵入式的测量方法,不仅具有实时在线测量的能力,还具有快速、原位、远程分析、多元素同时在线监测等特点,在燃烧测量领域具有重要的应用潜力。采用纳秒激光诱导击穿光谱技术对氢气和空气燃烧场的燃空当量比进行测量研究。氢气和空气在管内混合后,由射流口喷出形成射流燃烧火焰场。激光通过透镜聚焦到射流燃烧场中击穿并产生等离子体,其等离子体的发射光谱由光谱仪采集,实验发现光谱中H 656 nm和O 777 nm具有很强的发射强度,且光谱强度随着当量比的变化,呈现规律性变化趋势。因此,采用H 656 nm和O 777 nm的光谱分别标示氢气和空气,并将其比值作为燃空当量比的测量参量。实验在氢气空气混合均匀的低速流场中测量了不同当量比下H 656 nm与O 777 nm的光谱强度比值,并与当量比建立标定曲线,实验发现该标定曲线对燃烧场和非燃烧场同样适用。基于标定曲线,我们研究了存在外界掺混情况下,射流燃烧场的局部燃空当量比情况。在当量比1.0,流场速度为20 m·s^(-1)的射流燃烧场中,测量了射流中心位置不同高度的燃空当量比变化情况,并在相同工况下进行了数值模拟。模拟结果与实验测量吻合较好,验证了纳秒激光诱导击穿光谱技术测量氢气/空气混合气的燃空当量比的可行性。该方法可为氢气燃烧基础研究及数值模拟提供技术支持。

关键词：激光诱导击穿光谱氢能当量比模拟

Multiquadric Finite Difference (MQ-FD) Method and its Application

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Advances in Applied Mathematics and Mechanics 2009年第5期1卷 615-638页

作者： Yong yuan shan Chang Shu Ning Qin Department of Mechanical Engineering National University of Singapore10 Kent Ridge CrescentSingapore 119260Singapore Department of Mechanical Engineering University of SheffieldMappin StreetSheffield S13JDUnited Kingdom

The conventional finite difference(FD)schemes are based on the low order polynomial approximation in a local *** paper shows that when the polynomial approximation is replaced by the multiquadric(MQ)function approximation in the same region,a new FD method,which is termed as MQ-FD method in this work,can be *** paper gives analytical formulas of the MQ-FD method and carries out a performance study for its derivative approximation and solution of Poisson equation and the incompressible Navier-Stokes *** addition,the effect of the shape parameter c in MQ on the formulas of the MQFD method is *** approximation in one-dimensional space and Poisson equation in two-dimensional space are taken as model problems to study the accuracy of the MQ-FD ***,a lid-driven flow problem in a square cavity is simulated by the MQ-FD *** obtained results indicate that this method may solve the engineering problem very accurately with a proper choice of the shape parameter c.

关键词： MQ-FD method shape parameter central FD method

Application of exosome-derived noncoding RNAs in bone regeneration:Opportunities and challenges

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World Journal of Stem Cells 2022年第7期14卷 473-489页

作者： yuan-Zhong Ren shan-shan Ding Ya-Ping Jiang Hui Wen Tao Li Department of Emergency Trauma Surgery Luoyang Central Hospital Affiliated to Zhengzhou UniversityLuoyang 471000Henan ProvinceChina Department of Geriatrics Luoyang Central Hospital Affiliated to Zhengzhou UniversityLuoyang 471000Henan ProvinceChina Department of Oral Implantology The Affiliated Hospital of Qingdao UniversityQingdao 266000Shandong ProvinceChina Department of Joint Surgery The Affiliated Hospital of Qingdao UniversityQingdao 266003Shandong ProvinceChina

With advances in the fields of regenerative medicine,cell-free therapy has received increased *** have a variety of endogenous properties that provide stability for molecular transport across biological barriers to cells,as a form of cell-to-cell communication that regulates function and *** addition,exosomes are an important component of paracrine signaling in stemcell-based therapy and can be used as a stand-alone therapy or as a drug delivery *** remarkable potential of exosomes has paved the pathway for cell-free treatment in bone *** are enriched in distinct noncoding RNAs(ncRNAs),including microRNAs,long ncRNAs and circular *** ncRNAs have multiple *** expression of ncRNA in exosomes is associated with the regenerative potential and development of various diseases,such as femoral head osteonecrosis,myocardial infarction,and *** there is increasing evidence that exosome-derived ncRNAs(exoncRNAs)have the potential for bone regeneration,the detailed mechanisms are not fully ***,we review the biogenesis of exo-ncRNA and the effects of ncRNAs on angiogenesis and osteoblast-and osteoclast-related pathways in different ***,there are still many unsolved problems and challenges in the clinical application of ncRNA;for instance,production,storage,targeted delivery and therapeutic potency *** in exo-ncRNA methods and design will promote the development of therapeutics,revolutionizing the present landscape.

关键词： Exosomes Non-coding RNA Bone Osteogenesis Angiogenesis Osteoclasts

A New Stilbene from Cercis chinensis Bunge

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Journal of Integrative Plant Biology 2005年第8期47卷 1021-1024页

作者： yuan LI Dong-Ming ZHANG Shi-shan YU Institute of Materia Medica Chinese Academy of Medical Sciences and Peking Union Medical College Beijing 100050 China

To study new natural products, we used ODS （YMC, Kyoto, Japan） and silica gel column chromatography to separate compounds in Cercis chinensis Bunge （Leguminosae）. A new stilbene, trans- 3, 5, 3＇, 4＇-tetrahydroxy-4-methylstilbene （1）, along with 10 known compounds, namely piceatannol （2）, dihydromyricetin （3）, catechin （4）, dihydrorobinetin （5）, menisdaurin （6）, lithospermoside （7）, teatannin （8）, dasycarponin （9）, β-sitosterol （10）, and daucosterin （11）, was isolated from C. chinensis. Their structures were elucidated on the basis of spectroscopic evidence. Compounds 2-6 and 9 were isolated from the genus Cercis Linn. for the first time.

关键词： Cercis chinensis Leguminosae trans-3, 5, 3', 4'-tetrahydroxy-4-methylstilbene.

不同海拔高度下电晕放电等离子体粒子特性的仿真研究

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原子与分子物理学报 2025年第3期42卷 94-100页

作者：冷雪健金福宝马山刚陈科元青海大学能源与电气工程学院西宁810000

电晕放电作为等离子体的一种重要获取手段,它的放电特性及其降解能力与所处空气环境有着密切的关系.为了得到不同海拔高度对电晕放电特性和等离子体降解能力的影响,本文通过COMSOL软件基于流体动力学模型,对不同海拔高度的放电模型进行... 详细信息

电晕放电作为等离子体的一种重要获取手段,它的放电特性及其降解能力与所处空气环境有着密切的关系.为了得到不同海拔高度对电晕放电特性和等离子体降解能力的影响,本文通过COMSOL软件基于流体动力学模型,对不同海拔高度的放电模型进行数值模拟计算.分别对电流波形、影响等离子体降解能力的电子密度、平均电子能量等物理量随海拔高度变化的规律进行研究.结果表明,海拔越高,气压越低,环境温度越低,电流脉冲峰值越高,频率越高,脉冲启动时间越提前.脉冲波形的上升时间减小、下降时间增大.同时,电子密度以及平均电子能量也会随着海拔高度的升高而增强.

关键词：等离子体电晕放电 COMSOL仿真电子密度

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Conductivity and chemical stability of SrCe_(0.92)Nb_(0.03)Tm_(0.05)O_(3-δ) membrane prepared by modified sol-gel method

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Chinese Chemical Letters 2012年第8期23卷 957-960页

作者： Wen Hui yuan Chun shan Dong Li Li School of Chemistry and Chemical Engineering South China University of TechnologyGuangzhou 510640China College of Environmental Science and Engineering South China University of TechnologyGuangzhou 510640China

SrCe0.92 Nb 0.03 Tm0.05 O 3-δ powders were synthesized by a modified sol-gel method using citrate as a chelating agent.X-ray diffraction（XRD） analysis verified SrCe 0.92 Nb 0.03 Tm 0.05 O 3-δ powders and membranes consisting of a single perovskite *** morphologies of the sintered membranes were investigated by using scanning electron microscopy（SEM） *** tests demonstrated that the Nb introduction into doped strontium cerate greatly enhanced the chemical *** conductivities of SrCe 0.92 Nb 0.03 Tm 0.05 O 3-δ and SrCe 0.95 Tm 0.05 O 3-δ were measured by the four-point DC method under 10% H 2 /He atmosphere and temperatures（700-900℃）.With a maximum conductivity of 0.0067 S cm^-1 at 900℃,the total electrical conductivity of SrCe 0.92 Nb 0.03 Tm 0.05 O 3-δ increases with increasing *** H 2 permeation flux of SrCe 0.92 Nb 0.03 Tm 0.05 O 3-δ is 0.035 mL cm-2 min-1 when 40% H 2 /He and Ar were used respectively as the feed and sweeping gases at 900℃.

关键词： Strontium cerate Chemical stability Niobium Electrical conductivity

Microstructure evolution and phase transformation of traditional cast and spray-formed hypereutectic aluminium-silicon alloys induced by heat treatment

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International Journal of Minerals,Metallurgy and Materials 2010年第3期17卷 297-306页

作者： Long-gang Hou yuan-hua Cai Hua Cui Ji-shan Zhang State Key Laboratory for Advanced Metals and Materials University of Science and Technology Beijing Beijing 100083 China School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China

Microstructural evolution and phase transformation induced by different heat treatments of the hypereutectic aluminium-silicon alloy, Al-25Si-5Fe-3Cu （wt%, signed as 3C）, fabricated by traditional cast （TC） and spray forming （SF） processes, were investigated by differential scanning calorimetry （DSC） and scanning electron microscopy （SEM） combined with energy dispersive X-ray spectroscopy and X-ray diffraction techniques. The results show that A17Cu2Fe phase can be formed and transformed in TC- and SF-3C alloys between 802-813 K and 800-815 K, respectively. The transformation from β-Al5FeSi to δ-Al4FeSi2 phase via peritectic reaction can occur at around 858-870 K and 876-890 K in TC- and SF-3C alloys, respectively. The starting precipitation temperature of δ-Al4FeSi2 phase as the dominant Fe-bearing phase in the TC-3C alloy is 997 K and the exothermic peak about the peritectic transformation of δ-Al4FeSi2→β-Al5FeSi is not detected in the present DSC experiments. Also, the mechanisms of the microstructural evolution and phase transformation are discussed.

关键词： hypereutectic Al-Si alloy spray forming cast microstructure phase transformation