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Electronic Structure of High-Pressure Alumina Polymorphs

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Chinese Physics Letters 2000年第6期17卷 441-443页

作者： LIU Xiao-Lei duan wen-hui GU Bing-Lin Department of Physics Tsinghua UniversityBeijing 100084

Electronic properties are investigated for three alumina polymorphs(corundum,Rb_(2)O_(3)(Ⅱ)and Pbnm perovskite),which are predicted as the stable structures under different pressure range,by means of the first-principles molecular dynamics method within local density functional *** similarity in electronic properties of the polymorphs of alumina is *** effect of possible phase transitions on ruby(Cr^(+3)-doped Al_(2)O_(3))fluorescences is discussed.

关键词： (Ⅱ) perovskite similarity

Role of Ga-doping in iron-gallium alloy clusters

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Chinese Physics B 2012年第2期21卷 461-468页

作者： Tang Pei-Zhe Liu Hai-Tao Zhu Jie Wang Shan-Ying duan wen-hui Department of Physics Tsinghua UniversityBeijing 100084China The Key Laboratory of Computational Physics Institute of Applied Physics and Computational MathematicsBeijing 100088China State Key Laboratory for Advanced Metals and Materials University of Science and Technology BeijingBeijing 100083China

The structural and magnetic properties of Fen-mCam （n = 3 - 6, m = 0 - 2; n = 13, m = 0 - 3） alloy clusters have been studied using density functional theory. The substitutional doping is favourable for small clusters with up to six atoms at low Ga concentration and substitutional Ga atoms in 13-atom clusters prefer surface sites. The Ca-doping generally could reduce the energetic stability but enhance the electronic stability of Fe clusters, along with a decrease of the local magnetic moments of Fe atoms around Ca dopants. These findings provide a microscopic insight into Fe-Ga alloys which are well：known magnetostriction materials.

关键词： iron gallium alloy clusters density functional theory stability magnetic properties

Combination of Activating Blood Circulation and Detoxifying Chinese Medicines Played an Anti-Inflammatory Role in Unstable Angina Patients after Percutaneous Coronary Intervention: A Multicenter, Open-Labeled, Randomized Controlled Trial

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Chinese Journal of Integrative Medicine 2021年第11期27卷 803-810页

作者： MA Xiao-juan duan wen-hui ZHANG Ying GAO Jie GUAN Bao-yi CHEN Ke-ji SHI Da-zhuo National Clinical Research Center for Chinese Medicine Cardiology Xiyuan HospitalChina Academy of Chinese Medical SciencesBeijing100091China Cardiovascular Diseases Center Xiyuan HospitalChina Academy of Chinese Medical SciencesBeijing100091China

Objective To investigate the combined anti-inflammatory effect of activating blood circulation and detoxifying Chinese medicines in unstable angina(UA)*** This study was an open-labeled,randomized controlled trial conducted in 5 centers in Beijing.A total of 154 patients were randomized into two groups at a 1:1 ratio by random *** on the conventional treatment,patients in the activating blood circulation(ABC)group were treated with Guanxin Danshen Droping Pill(冠心丹参滴丸,0.4 g,thrice daily),and patients in the activating blood circulation and detoxifying(ABCD)group were treated with Guanxin Danshen Droping Pill(0.4 g,thrice daily)and Andrographis tablet(0.2 g,thrice daily)for 4 *** primary outcome was the serum level of high sensitive C reaction protein(hs-CRP),and the secondary outcome index included the serum levels of tumor necrosis factorα(TNF-α),interleukin 6(IL-6),soluble CD40 ligand(sCD40L),thrombomodulin(TM),the score of angina pectoris,the score of blood stasis syndrome,and the score of Chinese medicine symptoms,observed at week 0 and week *** A total of 144 patients completed the trial(ABC group,n=70;ABCD group,n=74).There were no significant differences in the clinical baseline characteristics between the two *** compared with the ABC group,ABCD group showed better performance in reducing the level of inflammatory factors,especially hs-CRP(P<0.05),IL-6(P<0.01)and TNF-α(P<0.01).In term of clinical symptoms,ABCD group played a better role in improving the scores of angina pectoris and blood stasis syndrome than ABC group(all P<0.05).Conclusions The combination of Guanxin Danshen Dropping Pill and Andrographis tablet exert significant anti-inflammatory effect on UA patients,which is superior to single Guanxin Danshen Dropping Pill.(Registration ***-TRC-13004072)

关键词： Chinese medicine unstable angina inflammation randomized controlled trial

Cluster Model for p-Type Doping of ZnSe

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Chinese Physics Letters 1997年第7期14卷 528-530页

作者： REN Tian-ling ZHU Jia-lin XIONG Jia-jiong duan wen-hui WANG Fu-he Department of Physics Tsinghua UniversityBeijing 100084 Institute of Physics Chinese Academy of SciencesBeijing 100080

Cluster model with DV-Xαmethod is used to study the structural and electronic properties of the p-type doping of *** is found that there is Jahn-Teller distortion for P doping and almost no Jahn-Teller distortion for N doping,and that the impurity levels with respect to the maximum of valence band are 118 and 96meV for N and P doping,*** reasons why N can serve as a better dopant than P for p-type ZnSe are discussed.

关键词： ZnSe dopant doping

基于细观结构性能和尺度的混凝土材料层次尺寸效应解析理论

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水利学报 2019年第11期50卷 1392-1399页

作者：李冬金浏杜修力刘晶波 duan wen-hui 清华大学土木系北京100084 莫纳什大学土木系维多利亚州3800 北京工业大学城市减灾与防灾防护教育部重点实验室北京100124

本文以细观为基本研究尺度,认为混凝土材料层次尺寸效应主要根源于粗骨料、砂浆以及界面等细观结构性能和尺度的不确定性。首先,基于建立的能够考虑细观结构影响的混凝土I-型裂缝断裂破坏分析模型,采用理论解析法对不同级配混凝土宏观... 详细信息

本文以细观为基本研究尺度,认为混凝土材料层次尺寸效应主要根源于粗骨料、砂浆以及界面等细观结构性能和尺度的不确定性。首先,基于建立的能够考虑细观结构影响的混凝土I-型裂缝断裂破坏分析模型,采用理论解析法对不同级配混凝土宏观力学性能预测方法进行了修正;进而,提出了一套混凝土材料层次尺寸效应解析理论,并分析了混凝土宏观力学性能随细观结构性能和尺度的变化行为。分析结果表明:单轴拉伸加载条件下,强骨料夹杂混凝土中界面力学性能、骨料含量和最大骨料粒径均显著影响细观断裂裂缝中界面裂缝的占比,从而影响到混凝土宏观力学性能随细观结构性能和尺度的变化行为。

关键词：混凝土尺寸效应细观力学断裂力学

低维纳米材料量子热输运与自旋热电性质——非平衡格林函数方法的应用

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物理学报 2015年第18期64卷 82-102页

作者：陈晓彬段文晖清华大学物理系北京100084

低维材料不断涌现的新奇性质吸引着科学研究者的目光.除了电子的量子输运行为之外,人们也陆续发现和确认了热输运中显著的量子行为,如热导低温量子化、声子子带、尺寸效应、瓶颈效应等.这些小尺度体系的热输运性质可以很好地用非平衡格... 详细信息

低维材料不断涌现的新奇性质吸引着科学研究者的目光.除了电子的量子输运行为之外,人们也陆续发现和确认了热输运中显著的量子行为,如热导低温量子化、声子子带、尺寸效应、瓶颈效应等.这些小尺度体系的热输运性质可以很好地用非平衡格林函数来描述.本文首先介绍了量子热输运的特性、声子非平衡格林函数方法及其在低维纳米材料中的研究进展;其次回顾了近年来在一系列低维材料中发现的热-自旋输运现象.这些自旋热学现象展现了全新的热电转换机制,有助于设计新型的热电转换器件,同时也给出了用热产生自旋流的新途径;最后介绍了线性响应理论以及在此理论框架下结合声子、电子非平衡格林函数方法进行的一些有益的探索.量子热输运的研究对热效应基础研究以及声子学器件、能量转换器件的发展有着不可替代的重要作用.

关键词：量子热输运自旋热学自旋热电非平衡格林函数

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回溯推理与经济解释

自然辩证法研究 2005年第8期21卷 5-8,32页

作者：段文辉武汉大学哲学学院湖北武汉430072

皮尔士提出的回溯推理是根据事实尝试性地提出理论假说,应用演绎推理从前提推出一些结论,作出预言,然后,根据实验来验证。如果预言得到实验的证实,那么,我们可以在一定程度上接受这一假说,把它转化为理论。回溯推理是一类独立的逻辑推... 详细信息

皮尔士提出的回溯推理是根据事实尝试性地提出理论假说,应用演绎推理从前提推出一些结论,作出预言,然后,根据实验来验证。如果预言得到实验的证实,那么,我们可以在一定程度上接受这一假说,把它转化为理论。回溯推理是一类独立的逻辑推理形式,其特点在于作出最佳解释。最佳解释推理要求具备一致性、简单性、类比性等特点。回溯推理在经济解释和经济学方法论中比归纳和演绎更为适用。

关键词：回溯推理归纳演绎最佳解释推理一致性简单性类比性先验实在论因果机制

Design of multifunctional interfaces on ceramic solid electrolytes for high-performance lithium-air batteries

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Green Energy & Environment 2025年第1期10卷 183-192页

作者： Yunxin Shi Ziyang Guo Changhong Wang Mingze Gao Xiaoting Lin hui duan Yonggang Wang Xueliang Sun College of Energy Material and Chemistry College of Chemistry and Chemical EngineeringInner Mongolia UniversityHohhot010021China Department of Mechanical and Materials Engineering Western UniversityLondonONN6A 5B9Canada Department of Chemistry and Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials Institute of New EnergyiChEM(Collaborative Innovation Center of Chemistry for Energy Materials)Fudan UniversityShanghai200433China Eastern Institute for Advanced Study Eastern Institute of TechnologyNingboZhejiang315100China

High-energy-density lithium(Li)–air cells have been considered a promising energy-storage system,but the liquid electrolyte-related safety and side-reaction problems seriously hinder their *** address these above issues,solid-state Li–air batteries have been widely ***,many commonly-used solid electrolytes generally face huge interface impedance inLi–air cells and also showpoor stability towards ambient air/Li ***,we fabricate a differentiating surface-regulated ceramic-based composite electrolyte(DSCCE)by constructing disparately LiI-containing polymethyl methacrylate(PMMA)coating and Poly(vinylidene fluoride-co-hexafluoropropylene)(PVDF-HFP)layer on both sides of Li_(1.5)Al_(0.5)Ge_(1.5)(PO_(4))_(3)(LAGP).The cathode-friendly LiI/PMMA layer displays excellent stability towards superoxide intermediates and also greatly reduces the decomposition voltage of discharge products in Li–air ***,the anode-friendly PVDF-HFP coating shows low-resistance properties towards ***,Li dendrite/passivation derived from liquid electrolyte-induced side reactions and air/I-attacking can be obviously suppressed by the uniformand compact composite *** a result,the DSCCE-based Li–air batteries possess high capacity/low voltage polarization(11,836mAh g^(-1)/1.45Vunder 500mAg^(-1)),good rate performance(capacity ratio under 1000mAg^(-1)/250mAg^(-1) is 68.2%)and longterm stable cell operation(~300 cycles at 750 mA g^(-1) with 750 mAh g^(-1))in ambient air.

关键词： Li-air batteries Li_(1.5)Al_(0.5)Ge_(1.5)(PO_(4))_(3) Polymers Composite electrolyte Ambient air

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纳米材料热传导中的新奇物理效应

物理 2020年第10期49卷 668-678页

作者：张刚段文晖新加坡高性能计算研究院新加坡138632 清华大学物理系北京100084

纳米尺度热传导是物理科学、材料科学和工程热物理等相关学科的研究热点。除基础研究上的意义外,这个方向的研究在微纳米器件温度控制、新能源、热防护等重大工程技术领域也有着重要的应用价值。文章主要介绍一维、二维纳米材料(包括纳... 详细信息

纳米尺度热传导是物理科学、材料科学和工程热物理等相关学科的研究热点。除基础研究上的意义外,这个方向的研究在微纳米器件温度控制、新能源、热防护等重大工程技术领域也有着重要的应用价值。文章主要介绍一维、二维纳米材料(包括纳米管、纳米线、石墨烯及其他二维材料)的热传导性质。由于篇幅所限,文章集中讨论在低维体系热传导中的新奇物理效应,如碳纳米管热导率随长度的发散行为,硅纳米线中的声子相干性,以及石墨烯热传导性质的尺寸效应。文章侧重强调低维纳米材料热传导与宏观体材料热传导特性的本质区别。

关键词：热传导碳纳米管半导体纳米线石墨烯二维材料