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Anisotropic elastic properties and ideal uniaxial compressive strength of TiB_2 from first principles calculations

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Chinese Physics B 2018年第7期27卷 443-449页

作者： Min Sun chong-yu wang Ji-Ping Liu School of Material Science and Engineering Beijing Institute of TechnologyBeijing 100081China Department of Physics Tsinghua UniversityBeijing 100084China

The structural, anisotropic elastic properties and the ideal compressive and tensile strengths of titanium diboride （TiB2） were investigated using first-principles calculations based on density functional theory. The stress-strain relationships of TiB2 under 〈10i0〉, 〈12i0〉, and 〈0001〉 compressive loads were calculated. Our results showed that the ideal uniaxial compressive strengths are ｜σ〈02i0〉）｜ = 142.96 GPa, ｜σ〈0001〉 ] = 188.75 GPa, and ｜σ〈10i0〉｜ = 245.33 GPa, at strains -0.16, -0.32, and -0.24, respectively. The variational trend is just the opposite to that of the ideal tensile strength with σ〈10i0〉 = 44.13 GPa, σ〈0001〉 = 47.03 GPa, and σ〈i2i0〉 = 56.09 GPa, at strains 0.14, 0.28, and 0.22, respectively. Furthermore, it was found that TiB2 is much stronger under compression than in tension. The ratios of the ideal compressive to tensile strengths are 5.56, 2.55, and 4.01 for crystallographic directions （10i0）, 〈12i0〉, and 〈0001〉, respectively. The present results are in excellent agreement with the most recent experimental data and should be helpful to the understanding of the compressive property of TiB2.

关键词： ideal compressive strength electronic structure elastic property first principles calculation

Dependence of mechanical properties on the site occupancy of ternary alloying elements in γ'-Ni3Al: Ab initio description for shear and tensile deformation

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Chinese Physics B 2020年第7期29卷 560-566页

作者： Minru Wen Xing Xie Huafeng Dong Fugen Wu chong-yu wang School of Physics and Optoelectronic Engineering Guangdong University of TechnologyGuangzhou 510006China School of Materials and Energy Guangdong University of TechnologyGuangzhou 510006China Department of Physics Tsinghua UniversityBeijing 100084China

The site occupancy behavior of ternary alloying elements inγ'-Ni3Al(a key strengthening phase of commercial Ni-based single-crystal superalloys)can change with temperature and alloy composition owing to the effect of *** a total-energy method based on density functional theory,the dependence of tensile and shear behaviors on the site preference of alloying elements inγ'-Ni3Al were investigated in *** results demonstrate that Fe,Ru,and Ir can significantly improve the ideal tensile and shear strength of theγ'phase when occupying the Al site,with Ru resulting in the strongest *** contrast,elements with fully filled d orbitals(i.e.,Cu,Zn,Ag,and Cd)are expected to reduce the ideal tensile and shear *** calculated stress-strain relationships of Ni3Al alloys indicate that none of the alloying elements can simultaneously increase the ideal strength of theγ'phase for both Ni1-site and Ni2-site *** addition,the charge redistribution and the bond length of the alloying elements and host atoms during the tensile and shear processes are analyzed to unveil the underlying electronic mechanisms.

关键词： stress-strain relations transition-metal elements γ'-Ni3Al first-principles calculations

Novel structures and mechanical properties of Zr_(2)N:Ab initio description under high pressures

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Chinese Physics B 2021年第1期30卷 434-442页

作者： Minru Wen Xing Xie Zhixun Xie Huafeng Dong Xin Zhang Fugen Wu chong-yu wang School of Physics and Optoelectronic Engineering Guangdong University of TechnologyGuangzhou 510006China School of Materials and Energy Guangdong University of TechnologyGuangzhou 510006China Department of Physics Tsinghua UniversityBeijing 100084China

With the formation of structural vacancies,zirconium nitrides(key materials for cutting coatings,super wearresistance,and thermal barrier coatings) display a variety of compositions and phases featuring both cation and nitrogen *** study presents a systematic exploration of the stable crystal structures of zirconium heminitride combining the evolutionary algorithm method and ab initio density functional theory calculations at pressures of 0 GPa,30 GPa,60 GPa,90 GPa,120 GPa,150 GPa,and 200 *** addition to the previously proposed phases P42/mnm-,Pnnn-,and Cmcm-Zr2 N,five new high-pressure Zr_(2)N phases of PA/nmm,IA/mcm,P2_(1)/m,P3 m1,and C2/m are *** enthalpy study of these candidate configurations reveals various structural phase transformations of Zr2 N under *** calculating the elastic constants and phonon dispersion,the mechanical and dynamical stabilities of all predicted structures are examined at ambient and high *** understand the structure-property relationships,the mechanical properties of all Zr_(2)N compounds are investigated,including the elastic moduli,Vickers hardness,and directional dependence of Young’s *** Cmncm-Zr2 N phase is found to belong to the brittle materials and has the highest Vickers hardness(12.9 GPa) among all candidate phases,while the I4/mcm-Zr2 N phase is the most ductile and has the lowest Vickers hardness(2.1 GPa).Furthermore,the electronic mechanism underlying the diverse mechanical behaviors of Zr2 N structures is discussed by analyzing the partial density of states.

关键词： phase transition phonon dispersion Zr_(2)N first-principles calculations

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额肌瓣悬吊术治疗重度先天性上睑下垂

国际眼科杂志 2013年第1期13卷 175-176页

作者：王崇玉南京爱尔眼科医院中国江苏省南京市210006

目的:探讨额肌瓣悬吊术治疗重度先天性上睑下垂的手术治疗效果。方法:对55例75眼重度先天性上睑下垂患者进行额肌瓣悬吊术,随访时间3～12(平均6)mo。结果:术后矫正满意69眼(92%),基本满意5眼(7%),欠矫1眼(1%),无明显过矫发生。结论:额... 详细信息

目的:探讨额肌瓣悬吊术治疗重度先天性上睑下垂的手术治疗效果。方法:对55例75眼重度先天性上睑下垂患者进行额肌瓣悬吊术,随访时间3～12(平均6)mo。结果:术后矫正满意69眼(92%),基本满意5眼(7%),欠矫1眼(1%),无明显过矫发生。结论:额肌瓣悬吊术是治疗重度先天性上睑下垂的一种疗效可靠的手术方法。

关键词：重度上睑下垂先天性额肌瓣悬吊术

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半球后注射曲安奈德治疗甲状腺相关眼病

国际眼科杂志 2013年第2期13卷 398-399页

作者：王崇玉南京爱尔眼科医院中国江苏省南京市210006

目的:评价半球后注射曲安奈德(triamcinolone acetonide,TA)治疗甲状腺相关眼病(thyroid associated ophthalmopathy,TAO)的临床效果。方法:对46例84眼甲状腺相关眼病患者以TA40mg加20g/L利多卡因0.5mL行眼部半球后注射,每3wk1次,连续4次为1疗程,1,3,6mo随访观察,记录眼部症状、体征情况。结果:患者43例自觉症状明显改善,眼球回退率83.6%,眼裂宽度缩小率85.2%,双眼视力改善率80.9%,眼球运动障碍、复视、斜视改善率80.5%。结论:半球后注射TA治疗甲状腺相关眼病效果明显,不良反应小,安全可靠。

关键词：曲安奈德甲状腺相关眼病半球后注射

Manganese carbonate stromatolites of the Ediacaran Doushantuo Formation in Chengkou,northern Yangtze Craton,China

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Journal of Palaeogeography 2021年第3期10卷 356-381页

作者： Yi Zhang Jian Li Long Chen Yi Wei Qiang Shi Dong-Ge wang Qing-Ming Wu Liao-yuan Song Meng Tian Hong-Wei Kuang Yong-Qing Liu Kaarel Mänd Hua-Qing Bai Zi-Liang Liu yu-chong wang Da-Wei Qiao Wen-Jun Zhu No.205 Geological Team Chongqing Bureau of Geology and Minerals ExplorationChongqing 402160China Institute of Geology Chinese Academy of Geological SciencesBeijing 100037China Department of Earth and Atmospheric Sciences University of AlbertaEdmontonAlberta T6G 2E8Canada Department of Geology University of TartuTartu 50411Estonia State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Chengdu University of TechnologyChengdu 610059Sichuan ProvinceChina PetroChina Xinjiang Oilfield Company Karamay 834099Xinjiang Uygur Autonomous RegionChina

The origin process of manganese ores remains unsolved *** the origins of stromatolites that contain manganese may be a key to deciphering the sedimentary environments and metallogenic processes of these ***,only a few manganese stromatolites have been discovered and described until *** are well developed in the manganese deposits,located near the top of the Ediacaran Doushantuo Formation in Chengkou area of chongqing,northern Yangtze Craton,but has not been explicitly studied;and whether they are true stromatolites or Epiphyton microbialites remains *** on field and core observations and thin section microscopy,the characteristics of five types of manganese stromatolites and their growth modes are described in detail in this *** results show that these stromatolites grew in a biostrome in shoal and lagoon environments and were syngenetic with oncolites and oolites on a carbonate ramp behind the *** stromatolites can be categorized into three forms:(1)stratiform;(2)columnar,which includes branched and columnar types;and(3)stratiform-columnar,which is a transitional *** on a criterion that the diameter is less than or greater than 1 mm,columnar stromatolites are further divided into micro-columnar(1 mm)columns,which display synchronous growth and are similar to *** shapes are mainly controlled by water depths and hydrodynamic *** greater the water depth,the more columnar the columns tend to *** strong hydrodynamic conditions decrease the growth rate of stromatolites,and they even stopped growth due to wave ***,pillared laminar textures(not Epiphyton),which consist of dendritic,micro-branched and microcolumnar stromatolites,are a common feature of the larger stratiform,stratiform-columnar and columnar *** alternations of laminae with different internal textures record subtle fluctuations in wat

关键词： Microbialites Manganese stromatolites Ediacaran Doushantuo Formation Yangtze Craton Growth mode

Application of Connectivity Map Database to Research on Chinese Materia Medica

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Chinese Herbal Medicines 2016年第2期8卷 117-120页

作者： Chao Lv yu-chong wang Run-hui Liu Wei-dong Zhang School of Pharmacy Second Military Medical University Shanghai Institute of Pharmaceutical Industry China State Institute of Pharmaceutical Industry

The connectivity map（CMAP） database is established initially to connect biology, chemistry, and clinical conditions, which helps to discover the connection of disease-gene-drug. The CMAP approach has been applied in the field of drug discovery and development, which is widely recognized. In recently years, CMAP analysis has been applied in the research on Chinese materia medica（CMM）. The study of CMM is facing a wide range of challenges, such as complicated ingredients, multiple targets, multiple pathways of action and complex functioning mechanism. The idea of employing CMAP in the CMM research has brought a new perspective for researchers and provides a systematic method for elucidating the mechanism of *** connectivity map （CMAP） database is established initially to connect biology, chemistry, and clinical conditions, which helps to discover the connection of disease-gene-drug. The CMAP approach has been applied in the field of drug discovery and development, which is widely recognized. In recently years, CMAP analysis has been applied in the research on Chinese materia medica （CMM）. The study of CMM is facing a wide range of challenges, such as complicated ingredients, multiple targets, multiple pathways of action and complex functioning mechanism. The idea of employing CMAP in the CMM research has brought a new perspective for researchers and provides a systematic method for elucidating the mechanism of CMM.

关键词： Chinese materia medica Chinese materia medica formula connectivity map establishing connectivity map database

Stratigraphic framework and sedimentary evolution during the Cryogenian-Ediacaran transition in northeastern Sichuan Basin,South China

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Petroleum Science 2024年第2期21卷 823-835页

作者： Yi Zhang Hong-Wei Kuang Yong-Qing Liu Qiang Shi Dong-Ge wang Ke-Ning Qi yu-chong wang Da-Wei Qiao Xiao-Shuai Chen Li-Zhi Wu Meng Tian Long Chen Yi Wei Liao-yuan Song Jian Li Zi-Gang Wu yun-Qian Liu Xuan-Chun Liu An-Qing Chen Zhi-Wei Liao Institute of Geology Chinese Academy of Geological SciencesBeijing100037China State Key Laboratory of Coal Mine Disaster Dynamics and Control School of Resources and Safety EngineeringChongqing UniversityChongqing400044China No.205 Geological Team Chongqing Bureau of Geology and Minerals ExplorationChongqing401121China chongqing Institute of Geological Survey Chongqing401122China Key Laboratory of Deep-time Geography and Environment Reconstruction and Applications of Ministry of Natural Resources Chengdu University of TechnologyChengdu610059SichuanChina

The northeastern Sichuan area in the northern Yangtze margin has unique Ediacaran geological records,especially the Doushantuo Formation(DST),and become a hot research area in recent ***,the Cryogenian-Ediacaran(C-E)boundary has not been precisely identified,which restricts the in-depth study of geological information during this crucial transitional period and is unfavorable for a systematic and complete understanding of the Yangtze Block and even the global paleogeographic *** study conducted stratigraphy,sedimentology,and chronostratigraphy to establish the stratigraphic framework and sedimentary evolution of the C-E transition strata in northeastern *** results showed that the Ediacaran sediments,without the cap dolomite,unconformably overlaid the Cryogenian sediments in the studied *** Member II of the DST,characterized by 50-160 m of red-green sandstone(approximately equivalent to the original Chengkou“Guanyinya Formation”),directly overlaid the Cryogenian sediments and displayed a 623±2.3 Ma maximum depositional age from the detrital zircon U-Pb *** stratigraphic correlations indicate that the C-E transition strata in northeastern Sichuan had a consistent lithological association and sedimentary sequence characteristics but differed from the Three ***,the upper Nantuo massive glacial diamictites transition to the icebergs rafted lonestone-bearing mudstones at the top,then change upward to DST barrier coast *** proposed DST of the northeastern Sichuan Basin was divided into three lithostratigraphic members without the regional Member I cap dolomite:(i)Member II purple-red,gray-green sandstone strata,(ii)MemberⅢblack mudstone strata,and(iii)Member IV P-Mn bearing *** the C-E transition,the study area experienced(i)the global deglaciation stage in the terminal Marinoan glaciation and(ii)the filling-leveling up stage with clastic rocks in the early ***,the early Ediacaran

关键词： Marinoan glaciation Doushantuo formation Cap dolomite Deglacial and coastal deposits Detrital zircon U-Pb dating

High-temperature-tolerant flexible supercapacitors: Gel polymer electrolytes and electrode materials

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Journal of Energy Chemistry 2025年第1期100卷 426-457页

作者： chong Peng Xinyi Huang Mingwei Zhao Shuling Liao Quanhong Yang Nianjun Yang Siyu yu School of Chemistry & Chemical Engineering Southwest University Nanoyang Group Tianjin Key Laboratory of Advanced Carbon and Electrochemical Energy Storage School of Chemical Engineering and Technology and Collaborative Innovation Center of Chemical Science and Engineering (Tianjin) Tianjin University Department of Chemistry & IMO-IMOMEC Hasselt University

The development of flexible supercapacitors(FSCs) capable of operating at high temperatures is crucial for expanding the application areas and operating conditions of supercapacitors. Gel polymer electrolytes and electrode materials stand as two key components that significantly impact the efficacy of hightemperature-tolerant FSCs(HT-FSCs). They should not only exhibit high electrochemical performance and excellent flexibility, but also withstand intense thermal stress. Considerable efforts have been devoted to enhancing their thermal stability while maintaining high electrochemical and mechanical performance. In this review, the fundamentals of HT-FSCs are outlined. A comprehensive overview of state-of-the-art progress and achievements in HT-FSCs, with a focus on thermally stable gel polymer electrolytes and electrode materials is provided. Finally, challenges and future perspectives regarding HT-FSCs are discussed, alongside strategies for elevating operational temperatures and *** review offers both theoretical foundations and practical guidelines for designing and manufacturing HT-FSCs, further promoting their widespread adoption across diverse fields.

关键词： Flexible supercapacitors High-temperature tolerance Gel polymer electrolytes Electrode materials