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Boosting the lithium-ion storage performance of perovskite Sr_(x)VO_(3-δ) via Sr cation and O anion deficient engineering

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Science Bulletin 2022年第22期67卷 2305-2315页

作者： xiaolei li Zifeng lin Na Jin Xiaojiao Yang Lei Sun Yuan Wang Lei Xie Xiping Chen li Lei Patrick Rozier Patrice Simon Ying liu College of Materials Science and Engineering Sichuan UniversityChengdu 610065China Key Laboratory of Neutron Physics and Institute of Nuclear Physics and Chemistry China Academy of Engineering PhysicsMianyang 621999China Institute of Atomic and Molecular Physics Sichuan UniversityChengdu 610065China CIRIMAT UMR CNRS 5085UniversitéToulouse III Paul SabatierToulouse 31062France RS2E Réseau Français sur le Stockage Electrochimique de l’EnergieFR CNRS 3459Amiens Cedex 80039France

Perovskite SrVO_(3) has been investigated as a promising lithium storage anode where the V cation plays the role of the redox center,combining excellent cycle stability and safe operating potential versus li metal plating,with limited ***,we demonstrate the possibility to boost the lithium storage properties,by reducing the non-redox active Sr cation content and fine-tuning the O anion vacancies while maintaining a non-stoichiometric Sr_(x)VO_(3-δ) perovskite *** investigations suggest that Sr vacancy can work as favorable li^(+) storage sites and preferential transport channels for guest li^(+) ions,contributing to the increased specific capacity and rate *** contrast,inducing O anion vacancy in Sr_(x)VO_(3-δ) can improve rate performance while compromising the specific *** experimental results confirm the enhancement of specific capacities by fine adjusting the Sr and O vacancies,with a maximum capacity of 444 mAh g^(-1) achieved with Sr_(0.63)VO_(3-δ),which is a 37%increase versus stoichiometric SrVO_(3).Although rich defects have been induced,Sr_(x)VO_(3-δ) electrodes maintain a stable perovskite structure during cycling versus a liFePO_(4) cathode,and the full-cell could achieve more than 6000 discharge/charge cycles with 80%capacity *** result highlights the possibility to use the cation defective-based engineering approach to design high-capacity perovskite oxide anode materials.

关键词： Perovskite Sr vacancy Non-stoichiometric Sr_(x)VO_(3-δ) O vacancy Defective-based engineering

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高速气流冲击柱状泡沫多孔体的传热特性分析

航空动力学报 2018年第8期33卷 1821-1829页

作者：李振环孙海锋李潇磊夏新林哈尔滨工业大学能源科学与工程学院哈尔滨150001

采用流体/多孔区域一体化单区域算法,数值研究了高速绕流条件下前置于圆柱体前缘表面的柱状泡沫多孔体内部的传热特性。基于蒙特卡罗法考虑多孔域内的辐射热效应,分析了变化多孔区域长度和多孔阻力特性对模型激波阻力和前缘多孔区域气... 详细信息

采用流体/多孔区域一体化单区域算法,数值研究了高速绕流条件下前置于圆柱体前缘表面的柱状泡沫多孔体内部的传热特性。基于蒙特卡罗法考虑多孔域内的辐射热效应,分析了变化多孔区域长度和多孔阻力特性对模型激波阻力和前缘多孔区域气动热的影响。结果表明:在圆柱体前缘安置一定长度及带有适当阻力特性的泡沫多孔材料,可同时减小整体激波阻力并降低前缘表面的气动热效应。在模拟工况下,无量纲长度1.0、黏性阻力系数0.2×10~7 m^(-2)及惯性阻力系数200m^(-1)的前缘泡沫多孔可减小激波阻力13.5%,降低约75%的前缘表面的平均气动热流密度。保持无量纲长度不变,减小泡沫多孔区域惯性阻力系数会降低激波阻力,但会略微增加前缘壁面气动热流密度。

关键词：高速绕流柱状泡沫多孔传热特性激波阻力气动热效应

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隔震结构复振型分解反应谱方法研究

振动与冲击 2022年第6期41卷 97-105页

作者：杨奎谭平陈华霆李晓磊广州大学广东省地震工程与应用技术重点实验室广州510405 广州大学工程抗震减震与结构安全教育部重点实验室广州510405

隔震结构一般具有非比例大阻尼特性,使得复振型分解反应谱方法的研究越来越重要。该研究通过隔震结构运动方程考虑非比例阻尼矩阵的耦合影响,根据复模态和平稳随机过程理论提出了隔震结构复振型分解反应谱方法,分别采用瑞利阻尼、振型... 详细信息

隔震结构一般具有非比例大阻尼特性,使得复振型分解反应谱方法的研究越来越重要。该研究通过隔震结构运动方程考虑非比例阻尼矩阵的耦合影响,根据复模态和平稳随机过程理论提出了隔震结构复振型分解反应谱方法,分别采用瑞利阻尼、振型叠加阻尼系数和阻尼比换算阻尼系数3种方法来组装形成4种不同的非比例阻尼矩阵,并以隔震结构特点分析了阻尼矩阵适用性;随后对比分析了在天然波反应谱作用下,不同阻尼矩阵组装方式下隔震层等效周期、等效阻尼比、对完全平方组合(CQC)和复振型完全平方组合(CCQC)方法计算精度的影响规律;最后基于设计反应谱CQC和设计反应谱CCQC反应谱方法,研究了隔震层不同等效周期和等效阻尼比对隔震结构的楼层位移、楼层剪力和楼层倾覆矩误差影响规律。研究结果表明,阻尼系数方法更适合用于非经典阻尼矩阵的构造,CQC反应谱方法在近场地震下不能准确反映实际响应,且其使用范围受限较多,而CCQC反应谱方法可以很好的反映隔震结果的地震响应。

关键词：隔震结构复振型完全平方组合(CCQC) 非比例阻尼反应谱

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含不对称茚满结构聚酰亚胺的合成与表征

高分子材料科学与工程 2020年第12期36卷 7-13,20页

作者：包春连李晓雷陈涛许保云上海化工研究院精细化工研究所上海200062

以双酚A为原料,通过有机合成制备含不对称茚满结构的二胺单体6-(4-氨基-2-三氟甲基)苯氧基-1-[4-(4-氨基-2-三氟甲基)苯氧基]苯基-1,3,3,-三甲基茚满,并与5种二酐通过化学亚胺化法制备含茚满结构聚酰亚胺。通过红外光谱、核磁共振、溶... 详细信息

以双酚A为原料,通过有机合成制备含不对称茚满结构的二胺单体6-(4-氨基-2-三氟甲基)苯氧基-1-[4-(4-氨基-2-三氟甲基)苯氧基]苯基-1,3,3,-三甲基茚满,并与5种二酐通过化学亚胺化法制备含茚满结构聚酰亚胺。通过红外光谱、核磁共振、溶解性能测试、紫外可见光谱、差示扫描量热分析、热重分析等对聚合物进行测试。结果表明,该系列聚酰亚胺室温下在低沸点溶剂如CHCl3,CH2Cl2,THF,丙酮等中也表现出非常优异的溶解性能;在450~760 nm范围内具有优异的光学性能,550 nm处透光率高达88.1%;玻璃化转变温度在228~265℃,5%热失重温度(N2氛围)在484~520℃,具有良好的热性能;拉伸强度为75.8~92.5 MPa,弹性模量为1.3~2.0 GPa,断裂伸长率为3.2%~10.8%,表现出良好的力学性能。

关键词：聚酰亚胺茚满结构溶解性能光学性能热性能

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超疏水表面减阻特性的研究进展

润滑与密封 2016年第10期41卷 116-122页

作者：李小磊张会臣大连海事大学交通运输装备与海洋工程学院辽宁大连116026

超疏水表面具有减阻效果,在提高管道传输效率、降低水下航行体和微流体器件中流动阻力等方面有着广阔的应用前景。介绍超疏水表面的制备、滑移理论以及减阻特性的研究,讨论微尺度下表面润湿性、表面微结构和流场流动状态对壁面减阻的影... 详细信息

超疏水表面具有减阻效果,在提高管道传输效率、降低水下航行体和微流体器件中流动阻力等方面有着广阔的应用前景。介绍超疏水表面的制备、滑移理论以及减阻特性的研究,讨论微尺度下表面润湿性、表面微结构和流场流动状态对壁面减阻的影响,对超疏水壁面减阻的物理机制进行总结,并指出气体层不连续模型和气穴模型是分别适用于光滑疏水表面和带微结构超疏水表面的减阻模型。介绍超疏水表面减阻特性的一些应用,提出将超疏水表面应用到微流体系统中面临的问题,如微通道壁面疏水性的制备及其减阻效果的耐久性。

关键词：超疏水表面减阻表面润湿性微结构流场

Type I vaccine-derived polioviruses in China from 1995 to 2019

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Biosafety and Health 2019年第3期1卷 155-158页

作者： Yong Zhang Shuangli Zhu Dongmei Yan Dongyan Wang xiaolei li Hui Zhu Hongqiu An Wenbo Xu WHO WPRO Regional Polio Reference Laboratory and National Laboratory for Poliomyelitis National Health Commission Key Laboratory for BiosafetyNational Health Commission Key Laboratory for Medical VirologyNational Institute for Viral Disease Control and PreventionChinese Center for Disease Control and PreventionBeijing 102206China Center for Biosafety Mega-Science Chinese Academy of SciencesWuhan 430071China

A nation-wide case surveillance was conducted in China since 1995 for the objective of identifying acute flaccid paralysis(AFP)in children so that potential wild polioviruses and vaccine-derived poliovirus(VDPV)could be identified on *** outbreaks associated with type I circulating VDPVs,eight native independent type I ambiguous VDPVs(aVDPV),and one imported aVDPV were identified during the AFP case surveillance in China from 1995 to *** VP1 coding region of the Chinese type I VDPVs differed from the polio vaccine strain by 1.00%–3.75%(9–34 substitutions in 906 nucleotides).Most of the Chinese type I VDPV strains shared 4 amino acid substitutions in the neutralizing antigenic(NAg)sites:3 located at the BC loop,which formed the NAg site 1,and another at NAg site *** of the Chinese type I VDPVs identified during the AFP case surveillance were young VDPVs,which indicated a limited viral replication resulted from the administration of the initiating oral polio vaccine(OPV)*** can emerge and spread in isolated communities with immunity gaps and the circulation ceases following a mass immunization with *** such,high-quality surveillance permitted very early detection and response and it played a key role in stalling the widespread circulation of the emergent cVDPV strains in China.

关键词： Type I Vaccine-derived poliovirus Phylogenetic analysis Neutralizing antigenic sites

Associations between Sleep Duration and Cardiovascular Diseases: A Meta-review and Meta-analysis of Observational and Mendelian Randomization Studies

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Associations between Sleep Duration and Cardiovascular Disea...

基于微肋板伸缩疏水/超疏水表面设计及其润湿性调控

中国睡眠研究会第十四届全国学术年会

作者： Shanshan Wang Zhexi li Xiaoyu Wang Yujing Sun Guohua li Chenhao Zhao Wenhui Yuan Meng li xiaolei li Sizhi Ai The First Affiliated Hospital of Xinxiang Medical University

Purpose: The associations between sleep duration and cardiovascular diseases(CVDs) have been explored in many observational studies. However, the causality of sleep duration and many CVDs, such as coronary artery disease(CAD), heart failure(HF), and stroke, remains unclear. In the present study, we conducted a systematic meta-review and meta-analysis of the results of observational and Mendelian randomization(MR) studies to examine how sleep duration impact the risk of ***: We searched articles published in English and before September 10, 2021 in PubMed, Web of Science, and Embase. The articles were screened independently by two reviewers to minimize potential bias. We combined the meta-analyses of observational studies and 11 MR studies and summarized evidence of the effect of sleep duration on the risk of CAD, HF, stroke, and cardiovascular and all-cause ***: This Meta-review and Meta-analysis showed that a) evidence is accumulating that short sleep duration is a causal risk factor for CAD and HF;b) abundant evidence from observational studies supports that long sleep duration is associated with the risk of CAD, stroke, and mortality, and long sleep duration has no causal associations with stroke and CAD in the MR studies;the causation of long sleep duration and other CVDs should be further studied;c) emerging evidence indicates that increase in hours of sleep is associated with decreased risk of ***: In summary, our meta-review found that short sleep duration may be a causal risk factor for many CVDs. Although observational meta-analysis supported that long sleep duration is associated with the risk of CVDs, the causal association between long sleep duration and CVDs remains unclear. Our results suggested that extending sleep duration in sleep-deprived people may be beneficial for their cardiovascular health.

关键词：

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机械工程学报 2017年第5期53卷 167-174页

作者：李小磊张磊马晓雯张会臣大连海事大学交通运输装备与海洋工程学院大连116026

利用组装的方法制备了具有微肋板结构且肋板高度可调控的表面,利用自组装分子膜技术对表面进行低表面能修饰,利用机械式调控方法改变疏水/超疏水表面微肋板高度,实现表面润湿性调控。结果表明:设计的疏水/超疏水表面可通过机械式调控方... 详细信息

利用组装的方法制备了具有微肋板结构且肋板高度可调控的表面,利用自组装分子膜技术对表面进行低表面能修饰,利用机械式调控方法改变疏水/超疏水表面微肋板高度,实现表面润湿性调控。结果表明:设计的疏水/超疏水表面可通过机械式调控方法实现表面润湿性调控,且可实现连续调控。具有微肋板结构表面的接触角具有各向异性,液滴在垂直于微肋板方向上的接触角大于平行于微肋板方向上的接触角。基于机械式调控方法,在垂直于微肋板方向上,表面润湿性实现了弱疏水到强疏水甚至超疏水的可逆调控,平行于微肋板方向上的调控效果相对较弱。微肋板的最佳组合可在116.2°~151.4°范围内实现润湿性调控,通过改变微肋板高度可控制表面接触角为这一范围内的任意值。

关键词：表面润湿性疏水/超疏水表面机械式调控

高压下新型双“A”层MAX相V_(2)Ga_(2)C的密度泛函理论研究

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高压物理学报 2021年第3期35卷 49-54页

作者：王腾飞李小雷李露李东王军凯河南理工大学材料科学与工程学院河南焦作454003

基于密度泛函理论的第一性原理,研究了压强对双“A”层MAX相V_(2)Ga_(2)C晶体结构、弹性和电子性质的影响,并利用玻恩稳定准则预测了V_(2)Ga_(2)C力学稳定状态下的压强范围。计算结果表明:在0~70 GPa下,V_(2)Ga_(2)C的晶体结构处于力学... 详细信息

基于密度泛函理论的第一性原理,研究了压强对双“A”层MAX相V_(2)Ga_(2)C晶体结构、弹性和电子性质的影响,并利用玻恩稳定准则预测了V_(2)Ga_(2)C力学稳定状态下的压强范围。计算结果表明:在0~70 GPa下,V_(2)Ga_(2)C的晶体结构处于力学稳定状态;随着压强的增大,V_(2)Ga_(2)C的晶格常数和体积均有不同程度的缩小,a轴随压强的增大收缩得最快,晶胞体积收缩了24%左右;随着压强的增加,V_(2)Ga_(2)C材料的维氏硬度从0 GPa压强下的18.23 GPa减小为70 GPa压强下的2.30 GPa,在20.15 GPa时从脆性材料转变为韧性材料;V_(2)Ga_(2)C的态密度和能带结构等电子性质随压强的变化较小,即压强对V_(2)Ga_(2)C的电子性质影响不大。

关键词： MAX相 V_(2)Ga_(2)C 高压力学稳定性弹性性质电子性质