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钢木组合结构研究综述 预览
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作者 张如玉 杨宝磊 +1 位作者 李国东 郝丹青 《山西建筑》 2019年第11期52-53,共2页
对比研究了钢结构、木结构的特点,结果表明钢木组合结构在工程应用中更有优势。系统介绍了国内外对钢木组合结构的研究进展,对钢木组合结构的研究现状进行论述,归纳出钢木组合结构有待解决的问题。
关键词 钢木组合 结构 钢结构 木结构
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玲珑金矿田98#脉及其南北向构造、脉岩特征与盲矿体预测 预览
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作者 宋泉吾 李宁 张林 《世界有色金属》 2019年第15期164-165,共2页
本文分析了矿脉和南北向构造、脉岩的地质特征及其相互关系。据此,对盲矿体进行了定位预测并取得了良好效果。
关键词 98号脉 构造 脉岩 主断裂构造 断裂构造 盲矿体
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Synthesis, crystal structure and photocatalytic performance of polyoxometalate K13[Gd(GeW11O39)2]·34H2O
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作者 Haibin Liu Lin Bai +4 位作者 Limei Ai Wenshuang Dai Danfeng Zhang Qingyin Wu Renchun Zhang 《中国稀土学报:英文版》 SCIE EI CAS CSCD 2019年第6期617-621,共5页
A polyoxometalate K13[Gd(GeW11O39)2]·34 H2 O was synthesized and characterized by elemental analysis,IR spectroscopy, UV spectra, XRD and thermal gravimetric analysis. X-ray single-crystal structural analysis ind... A polyoxometalate K13[Gd(GeW11O39)2]·34 H2 O was synthesized and characterized by elemental analysis,IR spectroscopy, UV spectra, XRD and thermal gravimetric analysis. X-ray single-crystal structural analysis indicates that the title compound crystallizes in the triclinic crystal system. The heteropolyanion of [Gd(GeW11O39)2]13 consists of two [GeW11O39]8- vacant Keggin moieties linked via Gd3+. Photocatalytic performance of K13[Gd(GeW11O39)2]·34 H2 O in photodegradation of X-3 B was also studied.When the reaction time is 180 min, the decoloring rate reaches 71.19%. With the decrease of pH, the decolorization rate increases gradually. 展开更多
关键词 POLYOXOMETALATE KEGGIN STRUCTURE Crystal STRUCTURE PHOTOCATALYTIC performance Rare earths
Moho Structure of the Southwest Sub-Basin,South China Sea,from a Multichannel Seismic Reflection Profile NH973-1 预览
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作者 ZHANG Jinchang CHEN Jie HUANG Yanming 《中国海洋大学学报:英文版》 SCIE CAS CSCD 2019年第5期1105-1114,共10页
Moho structure provides important clues for understanding crustal structure,isostatic state and magmatic flux from mantle to surface.Across-basin Moho structure of the South China Sea(SCS)is important for understandin... Moho structure provides important clues for understanding crustal structure,isostatic state and magmatic flux from mantle to surface.Across-basin Moho structure of the South China Sea(SCS)is important for understanding crustal evolution mechanisms of both continental break-up and seafloor spreading processes.Southwest Sub-basin(SWSB)opened up the latest and has the closest continental margins,making it the best to study the across-basin structure.Multichannel seismic(MCS)reflection data of line NH973-1 that crosses SWSB in NW-SE direction were reprocessed in order to image Moho structure.In MCS data,Moho reflectors are observed in places,which were not revealed in prior researches.The Moho generally shows symmetric structure on both sides of the central rift valley(CRV)and with variations in crustal thickness.Around CRV,the Moho is 2 seconds depth in two-way travel time(TWTT)beneath the igneous basement,which corresponds to 7 km depth,indicating normal oceanic crustal accretion during the ending of seafloor spreading.Close to the continent-ocean boundary(COB),the Moho becomes shallow to 1 second depth in TWTT(3.5 km),implying strong crustal thinning towards the continent,probably because of poor magma supply at the beginning of seafloor spreading.At south COB,the Moho depth under the crust almost reaches zero,which could be explained as a result of exhumed mantle.In addition,two low-angle,deep-penetrating normal faults are observed at south COB.The faults cut across the Moho into the upper mantle,which may be attributed to lithospheric hyper-stretching at COB during continental break-up. 展开更多
关键词 MOHO STRUCTURE MULTICHANNEL seismic reflection CRUSTAL STRUCTURE South China Sea OCEANIC basin continent-ocean boundary
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浙江高校海洋学科专业结构与产业结构的适应性分析 预览
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作者 王贺元 《泉州师范学院学报》 2019年第1期78-82,共5页
海洋学科专业结构与海洋产业结构有着直接的互动联系。海洋学科专业结构的调整需要基于海洋产业结构来考量。此领域的研究,除了常规的量化范式,还需从整体层面考量二者的适应性。当前浙江高校的海洋学科专业结构某种程度上还无法适应海... 海洋学科专业结构与海洋产业结构有着直接的互动联系。海洋学科专业结构的调整需要基于海洋产业结构来考量。此领域的研究,除了常规的量化范式,还需从整体层面考量二者的适应性。当前浙江高校的海洋学科专业结构某种程度上还无法适应海洋产业结构转型升级的需要。基于此,需要建立高校海洋学科专业宏观决策机制、海洋学科专业结构与产业结构协同发展机制以及动态调整机制,以促进二者的可持续发展。 展开更多
关键词 海洋学科 专业结构 产业结构 适应性 浙江高校
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Conceptual design and update of the 128-channel μSR prototype spectrometer based on musrSim 预览
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作者 Zi-Wen Pan Jing-Yu Dong +5 位作者 Xiao-Jie Ni Lu-Ping Zhou Jing-Yu Tang Daniel E.Pooley Stephen P.Cottrell Bang-Jiao Ye 《核技术:英文版》 SCIE CAS CSCD 2019年第8期50-58,共9页
An experimental muon source(EMuS) will be built at the China Spallation Neutron Source(CSNS). In phase I of CSNS, it has been decided that EMuS will provide a proton beam of 5 kW and 1.6 GeV to generate muon beams. A ... An experimental muon source(EMuS) will be built at the China Spallation Neutron Source(CSNS). In phase I of CSNS, it has been decided that EMuS will provide a proton beam of 5 kW and 1.6 GeV to generate muon beams. A 128-channel muon spin rotation/relaxation/resonance(μSR) spectrometer is proposed as a prototype surface muon spectrometer in a sub-branch of EMuS. The prototype spectrometer includes a detection system, sample environment, and supporting mechanics. The current design has two rings located at the forward and backward directions of the muon spin with 64 detectors per ring. The simulation shows that the highest asymmetry of approximately 0.28 is achieved by utilizing two 10-mm-thick brass degraders. To obtain the optimal asymmetry, the two-ring structure is updated to a four-ring structure with 32 segments in each ring. An asymmetry of 0.42 is obtained through the simulation, which is higher than that of all the current μSR spectrometers in the world. 展开更多
关键词 EMUS μSR SPECTROMETER 128-Channel Two-ring STRUCTURE Four-ring STRUCTURE Asymmetry
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The art of two-dimensional soft nanomaterials
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作者 Caini Zheng Jinhui Zhu +3 位作者 Chongqing Yang Chenbao Lu Zhenying Chen Xiaodong Zhuang 《中国科学:化学英文版》 SCIE EI CAS CSCD 2019年第9期1145-1193,共49页
The discovery of graphene has triggered the explosive development of two-dimensional(2D) nanomaterials, including both inorganic and organic species. Benefiting from the simple elemental composition, inorganic 2D nano... The discovery of graphene has triggered the explosive development of two-dimensional(2D) nanomaterials, including both inorganic and organic species. Benefiting from the simple elemental composition, inorganic 2D nanomaterials were the center research in the past decade, which has long shadowed the research of 2D organic(or soft) nanomaterials. Although many kinds of2D soft nanomaterials have been successfully prepared, a unified definition for them is still impossible due to the complicate and quite different chemical structures between each other and even relying on totally different techniques to distinguish them. Since our first review on 2D soft nanomaterials in 2015, this field has moved forward with big success. In this review, we will focus on the development of 2D soft nanomaterials after 2015. In order to deliver better overview of this field, new and comprehensive classification is used in this review: 2D aromatic molecules, graphene and graphene nanoribbons, graphyne and graphdiyne,BxCyNznanosheets, 2D polymers, 2D supramolecules, crystalline 2D assemblies, 2D covalent organic frameworks, 2D metalorganic frameworks, sandwich-like 2D porous polymers, 2D polymer nanosheets, etc. The focus of this review lies on synthetic strategies and the challenges of characterization, definition and fundamental understanding. 展开更多
关键词 two dimensional SOFT material NANOSHEET LAYERED STRUCTURE sandwich-like STRUCTURE
矫直机的设计与结构分析 预览
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作者 宋磊 岳海波 《中国重型装备》 2019年第3期8-9,22共3页
介绍了酸洗退火生产线中矫直机的结构并进行设计分析,计算了矫直辊矫直力和电机功率。
关键词 矫直机 结构 设计 开口式机架结构
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The CALYPSO methodology for structure prediction
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作者 童群超 吕健 +1 位作者 高朋越 王彦超 《中国物理B:英文版》 SCIE EI CAS CSCD 2019年第10期22-29,共8页
Structure prediction methods have been widely used as a state-of-the-art tool for structure searches and materials discovery, leading to many theory-driven breakthroughs on discoveries of new materials. These methods ... Structure prediction methods have been widely used as a state-of-the-art tool for structure searches and materials discovery, leading to many theory-driven breakthroughs on discoveries of new materials. These methods generally involve the exploration of the potential energy surfaces of materials through various structure sampling techniques and optimization algorithms in conjunction with quantum mechanical calculations. By taking advantage of the general feature of materials potential energy surface and swarm-intelligence-based global optimization algorithms, we have developed the CALYPSO method for structure prediction, which has been widely used in fields as diverse as computational physics, chemistry, and materials science. In this review, we provide the basic theory of the CALYPSO method, placing particular emphasis on the principles of its various structure dealing methods. We also survey the current challenges faced by structure prediction methods and include an outlook on the future developments of CALYPSO in the conclusions. 展开更多
关键词 STRUCTURE PREDICTION CALYPSO method CRYSTAL STRUCTURE POTENTIAL ENERGY surface
Stability of the linear chain structure for 12C in covariant density functional theory on a 3D lattice
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作者 ZhengXue Ren ShuangQuan Zhang +3 位作者 PengWei Zhao Naoyuki Itagaki Joachim AMaruhn Jie Meng 《中国科学:物理学、力学、天文学英文版》 SCIE EI CAS CSCD 2019年第11期6-13,共8页
The stability of the linear chain structure of three α clusters for 12C against the bending and fission is investigated in the cranking covariant density functional theory, in which the equation of motion is solved o... The stability of the linear chain structure of three α clusters for 12C against the bending and fission is investigated in the cranking covariant density functional theory, in which the equation of motion is solved on a 3D lattice with the inverse Hamiltonian and the Fourier spectral methods. Starting from a twisted three α initial configuration, it is found that the linear chain structure is stable when the rotational frequency is within the range of ~2.0-~2.5 MeV. Beyond this range, the final states are not stable against fission. By examining the density distributions and the occupation of single-particle levels, however, these fissions are found to arise from the occupation of unphysical continuum with large angular momenta. To properly remove these unphysical continuum, a damping function for the cranking term is introduced. Eventually, the stable linear chain structure could survive up to the rotational frequency ~3.5 MeV, but the fission still occurs when the rotational frequency approaches ~4.0 MeV. 展开更多
关键词 COVARIANT density functional theory cranking model 3D LATTICE space linear chain STRUCTURE alpha-cluster STRUCTURE COLLECTIVE ROTATION 12C
Economic Growth and Interaction between Financial and Industrial Structure - Empirical Analysis on Provincial Panel Data 预览
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作者 Fangying Yao 《经济管理学刊:中英文版》 2019年第1期58-74,共17页
In recent years, China's economic growth speed has been slowing down, leading to the problems of overcapacity and unbalanced regional economic development, and the mismatch between industrial and financial structu... In recent years, China's economic growth speed has been slowing down, leading to the problems of overcapacity and unbalanced regional economic development, and the mismatch between industrial and financial structure is becoming intense. Therefore, this paper, starting with the relationship among economic growth, industrial structure and financial structure, summarizes the research by the former scholars. On this basis, by using data of 31 provincial panel data in China from 2007 to 2016, the article aims to find out the relationship between the industrial structure and economic growth, the relationship between the financial structure and economic growth and the relationship between the interaction of financial and industrial structure and economic growth. Finally, the corresponding policy recommendations are obtained following the systematical empirical conclusions. The conclusions of this paper are as follows:(1) developing indirect financing mode can effectively drive China's economic growth.(2) continuing to develop the second industry can play a catalytic role in the economic growth in most areas of China.(3) the interaction between the financial structure and the industrial structure can promote the economic growth significantly. However, the matching effect of the financial structure and industrial structure in China has not been completely formed, and the industrial upgrading should be guided to be structurally reformed through the policy. 展开更多
关键词 Industrial STRUCTURE FINANCIAL STRUCTURE ECONOMIC Growth Panel Data GLS Model
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Flux mechanism of compound flux on ash and slag of coal with high ash melting temperature
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作者 Chengli Wu Beibei Wang +1 位作者 Jiuqiang Zheng Hanxu Li 《中国化学工程学报:英文版》 SCIE EI CAS CSCD 2019年第5期1200-1206,共7页
The melting temperature of Z coal ash was reduced by adding calcium–magnesium compound flux(WCaO/WMgO=1). In the process of simulated coal gasification, the coal ash and slag were prepared. The transformation of mine... The melting temperature of Z coal ash was reduced by adding calcium–magnesium compound flux(WCaO/WMgO=1). In the process of simulated coal gasification, the coal ash and slag were prepared. The transformation of minerals in coal ash and slag upon the change of temperature was studied by using X-ray diffraction(XRD). With the increase of temperatures, forsterite in the ash disappears, while the diffraction peak strength of magnesium spinel increases,and the content of the calcium feldspar increases, then the content of the amorphous phase in the ash increases obviously. The species and evolution process of oxygen, silicon, aluminum, calcium, magnesium at different temperatures were analyzed by X-ray photoelectron spectroscopy(XPS). The decrease of the ash melting point mainly affects the structural changes of silicon, aluminum and oxygen. The coordination of aluminum and oxygen in the aluminum element structure, e.g., tetracoordinated aluminum oxide, was changed. Tetrahedral [AlO4] and hexacoordinated aluminoxy octahedral [AlO6] change with the temperature changing. The addition of Ca2+ and Mg2+ destroys silica chain, making bridge oxide silicon change into non-bridge oxysilicon;and bridge oxygen bond was broken and non-bridge oxygen bond was produced in the oxygen element structure. The addition of calcium and magnesium compound flux reacts with aluminum oxide tetrahedron, aluminum oxide octahedron and silicon tetrahedron to promote the breakage of the bridge oxygen bond. Ca2+ and Mg2+ are easily combined with silicon oxide and aluminum oxide tetrahedron and aluminum. Oxygen octahedrons combine with non-oxygen bonds to generate low-melting temperature feldspars and magnesite minerals, thereby reducing the coal ash melting temperatures. The structure of kaolinite and mullite was simulated by quantum chemistry calculation, and kaolinite molecule has a stable structure. 展开更多
关键词 COAL ASH and SLAG COMPOUND FLUX X-ray photoelectron spectroscopy Transformation of mineral STRUCTURE STRUCTURE of kaolinite and mullite
Export Performance of China: A Constant Market Share Analysis
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作者 Nidhi Bagaria Saba Ismail 《中国经济学前沿:英文版》 2019年第1期110-130,共21页
In the light of the fact that there has been substantial growth in China's exports in last three decades, particularly after China joined the WTO in 2001, this article investigates the major sources of China's... In the light of the fact that there has been substantial growth in China's exports in last three decades, particularly after China joined the WTO in 2001, this article investigates the major sources of China's export performance during 2002-2014 by using the constant market share (CMS) model. In this study, exports are further decomposed in three categories based on their technological intensity using Lail (2000) classification on 3 digit SITC Revision-3 data provided by UN Comtrade via WITS database. The categories are high technology, medium technology and low technology. It is found that growth of China's exports has, moreover, remained above world exports growth in all three categories during the period of study. The analysis reveals that export performance is mainly attributed to 让s competitive strength in the global market, though decreasing trend has been observed in the competitiveness of all three categories. Increasing cost of labor and appreciating RMB could be the causes behind decreasing competitiveness of Chinese exports. Product structure effect, on an average, has turned out to be negative in all the categories which is the most disturbing aspect of China's export performance. On the other hand, geographical structure effect has positive impact on export performance of high-technology based exports whereas it has negative impact on export performance of low-technology and medium-technology based exports. China being the world's largest exporter, decreasing competitiveness and wrong product structure effect could adversely influence its export performance in particular and its growth in general. 展开更多
关键词 CONSTANT MARKET SHARE (CMS) China's SHARE in world exports export performance MARKET SHARE EFFECT product STRUCTURE EFFECT geographical STRUCTURE EFFECT competitiveness HI-TECH
Insights into the Discrepancy between Single Molecule Experiments
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作者 周倩 张敏 +5 位作者 范洋涛 王育慷 鲍琳 赵光菊 陈虎 刘艳辉 《理论物理通讯:英文版》 SCIE CAS CSCD 2019年第6期753-763,共11页
Sharp bending as one of the mechanical properties of double-stranded DNA(dsDNA) on the nanoscale is essential for biological functions and processes. Force sensors with optical readout have been designed to measure th... Sharp bending as one of the mechanical properties of double-stranded DNA(dsDNA) on the nanoscale is essential for biological functions and processes. Force sensors with optical readout have been designed to measure the forces inside short, strained loops composed of both dsDNA and single-stranded DNA(ssDNA). Recent FRET singlemolecule experiments were carried out based on the same force sensor design, but provided totally contrary results. In the current work, Monte Carlo simulations were performed under three conditions to clarify the discrepancy between the two experiments. The criterion that the work done by the force exerted on dsDNA by ssDNA should be larger than the nearest-neighbor(NN) stacking interaction energy is used to identify the generation of the fork at the junction of dsDNA and ssDNA. When the contour length of dsDNA in the sensor is larger than its critical length, the fork begins to generate at the junction of dsDNA and ssDNA, even with a kink in dsDNA. The forces inferred from simulations under three conditions are consistent with the ones inferred from experiments, including extra large force and can be grouped into two different states, namely, fork states and kink states. The phase diagrams constructed in the phase space of the NN stacking interaction energy and excited energy indicate that the transition between the fork state and kink state is difficult to identify in the phase space with an ultra small or large number of forks, but it can be detected in the phase space with a medium number of forks and kinks. 展开更多
关键词 force sensor Monte Carlo simulation KINK STRUCTURE FORK STRUCTURE nearest-neighbouring STACKING interaction energy
Revisiting coherent structures in low-speed turbulent boundary layers 预览
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作者 Xianyang JIANG 《应用数学和力学:英文版》 SCIE EI CSCD 2019年第2期261-272,共12页
Coherent structures are essential for the momentum exchange and turbulence production in wall-bounded turbulent flows.Diversified coherent structures have been observed in turbulent boundary layers,and hairpin-based v... Coherent structures are essential for the momentum exchange and turbulence production in wall-bounded turbulent flows.Diversified coherent structures have been observed in turbulent boundary layers,and hairpin-based vortices dominate most of the relevant literature.However,there is no consensus yet on the origin and forming mechanism of hairpin vortices.Herein,five cornerstones pertaining to the framework of hairpin-based coherent structures are reviewed,and three different hairpin generation mechanisms are clarified.Next,the time-resolved tomographic particle image velocimetry(Tomo-PIV)is used in an early turbulent boundary layer(Reθ=420)to investigate the origin of hairpin vortices.The timelines reveal a triangular bulge in the low-speed streak(LSS),and the initial roll-up occurs at two sides of it.Meanwhile,the material surfaces manifest as a three-dimensional(3D)wave structure in the LSS,which may support the model of a soliton-like coherent structure(SCS).Subsequently,the method of Lagrangian-averaged vorticity deviation is used to detect early vortices.We find that the 3D wave structure is flanked by two vortices,thus confirming the roll-up of timelines and demonstrating the advantage of the Lagrangian criteria in capturing structures in complex flows.These results suggest that various coherent structures may evolve from the metamorphosis of 3D wave structures and their later interaction.Finally,the limitations of traditional experimental and post-processing tools are discussed. 展开更多
关键词 COHERENT STRUCTURE HAIRPIN vortex SOLITON-LIKE COHERENT structure(SCS)
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轻量化中基于应力驱动的单元网格构型匹配研究 预览
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作者 陈赛 纪小刚 +1 位作者 龚珍珍 何雪明 《现代制造工程》 CSCD 北大核心 2019年第4期1-6,共6页
为了实现结构体在满足力学性能前提下消耗最少材料,获得最轻重量的轻量化要求,提出一种基于应力驱动的单元网格构型匹配建模设计方法。将从单元网格构型库中选取的模型进行受力分析,得到不同单元网格构型所能承受的最大应力。对结构体... 为了实现结构体在满足力学性能前提下消耗最少材料,获得最轻重量的轻量化要求,提出一种基于应力驱动的单元网格构型匹配建模设计方法。将从单元网格构型库中选取的模型进行受力分析,得到不同单元网格构型所能承受的最大应力。对结构体建模进行受力分析得出结构体受力状态下三维空间应力值数据库,结合不同单元网格构型所能承受的最大应力进行匹配,实现结构体的轻量化设计。轻量化设计得到的结构体,不仅能够满足其力学性能.而且相比原来结构体的体积和重量减少了约48%,耗材更少。 展开更多
关键词 结构体 单元网格构型 应力驱动 匹配 轻量化
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Approach to 2′-(Dialkylamino)-1-alkyl-4′H-spiro[indoline-3,5′-oxazole]-2,4′-diones and 1,3-Oxazin-4-ones via Cyclization of Vilsmeier Salts withα-Hydroxy andβ-Carbonyl Amides
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作者 DAI Jianan LIU Bengen +4 位作者 WEI Zhonglin CAO Jungang LIANG Dapeng DUAN Haifeng LIN Yingjie 《高等学校化学研究:英文版》 SCIE CAS CSCD 2019年第2期216-220,共5页
A straiglitforward and efficient synthetic method of 2′-(dialkylammo)-l-alkyl-4′H-spiro[indoline-3,5′-oxazole]-2,4′-diones and 2-(dialkylamino)-5,6-dihydro-4H-naphtho[2,1-e][1,3]oxazin-4-one-derivatives have been ... A straiglitforward and efficient synthetic method of 2′-(dialkylammo)-l-alkyl-4′H-spiro[indoline-3,5′-oxazole]-2,4′-diones and 2-(dialkylamino)-5,6-dihydro-4H-naphtho[2,1-e][1,3]oxazin-4-one-derivatives have been developed from a-hydroxy andβ-carbonyl amides and various Vilsmeier salts.A wide range of heterocyclic compounds were obtained in excellent yields(up to 97%),which will provide promising candidates lor chemical biology and drug discovery. 展开更多
关键词 SPIROOXINDOLE unit 2-Oxazolin-4-ones CORE STRUCTURE 3-Oxazin-4-ones CORE STRUCTURE
Atomic pair distribution function research on Li2MnO3 electrode structure evolution
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作者 Yubo Yang Heng Su +5 位作者 Tianhao Wu Yuyuan Jiang Danmin Liu Pengfei Yan Haolai Tian Haijun Yu 《科学通报:英文版》 SCIE EI CSCD 2019年第8期553-561,共9页
The mechanism research of structure-related reactions on Li2MnO3 is important to enhance the electrochemical performance of lithium-manganese-rich layered oxides.Although there are some reports on the structure evolut... The mechanism research of structure-related reactions on Li2MnO3 is important to enhance the electrochemical performance of lithium-manganese-rich layered oxides.Although there are some reports on the structure evolution of Li2MnO3 during cycling process,the employed research techniques are very limited,mainly in/ex-situ X-ray diffraction,X-ray absorption and transmission electron microscopy.Here,atomic pair distribution function,a method to study the local atomic arrangement on the basis of average spectroscopic information,is used for the first time to study the local structure evolution of Li2MnO3 during electrochemical charge/discharge cycles.The results clearly demonstrate that Mn3+/Mn4+ redox couple is activated and Mn ions are reduced during discharging process.Some Mn ions in Mn layers can significantly migrate to Li layers and occupy the octahedral sites.As a result,a portion of inserted Li ions can occupy the face-shared tetrahedron sites,accompanied by the formation of local spinel-like structure.This work provides an important and suitable method based on the average spectroscopic information to investigate the local structure of electrode materials of lithium-ion batteries as well as other advanced battery systems. 展开更多
关键词 LI-ION battery Lithium-manganese-rich LAYERED OXIDES Local STRUCTURE PAIR distribution function STRUCTURE evolution
Preparation of pyramid-SiNWs binary structure with Ag nanoparticles-assisted chemical etching
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作者 Zi-Long Zhang Bo Wang +4 位作者 Yu Chen Yun-Hui Tang Xue-Mei Song Qing-Liu Li Hui Yan 《稀有金属:英文版》 SCIE EI CAS CSCD 2019年第4期312-315,共4页
It is an important way to improve the efficiency of solar cells by using the special microstructures of surface.In this work,a pyramid-silicon nanowires (pyramidSiNWs) binary structure was prepared on the silicon surf... It is an important way to improve the efficiency of solar cells by using the special microstructures of surface.In this work,a pyramid-silicon nanowires (pyramidSiNWs) binary structure was prepared on the silicon surfaces with the metal-assisted chemical etching (MACE) method.Scanning electron microscope (SEM) was used to observe the micromorphology of the pyramid-SiNWs binary structure.The formation mechanism of the binary structure was discussed.The role of Ag nanoparticles in MACE is considered to be the template and the catalyzer.The optical reflectivity of the silicon surfaces was studied with ultraviolet-visible (UV-Vis) spectrophotometer.Compared with the fiat silicon surface and the simple pyramidal structure,the silicon surfaces with the pyramid-SiNWs binary structure achieve a much lower reflectance in a wide range of wavelength.The effect of etching time as a parameter on the reflectivity was also discussed. 展开更多
关键词 Ag NANOPARTICLE PYRAMID STRUCTURE Silicon NANOWIRES BINARY STRUCTURE Reflectance
THE STRUCTURE-PRESERVING METHODS FOR THE DEGASPERIS-PROCESI EQUATION
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作者 Yuze Zhang Yushun Wang Yanhong Yang 《计算数学:英文版》 SCIE CSCD 2019年第4期475-487,共13页
This paper gives several structure-preserving schemes for the Degasperis-Procesi equation which has bi-Hamiltonian structures consisted of both complex and non-local Hamiltonian differential operators. For this sake, ... This paper gives several structure-preserving schemes for the Degasperis-Procesi equation which has bi-Hamiltonian structures consisted of both complex and non-local Hamiltonian differential operators. For this sake, few structure-preserving schemes have been proposed so far. In our work, based on one of the bi-Hamiltonian structures, a symplectic scheme and two new energy-preserving schemes are constructed. The symplecticity comes straightly from the application of the implicit midpoint method on the semi-discrete system which is proved to remain Hamiltonian, while the energy conservation is derived by the combination of the averaged vector field method of second and fourth order, respectively. Some numerical results are presented to show that the three schemes do have the advantages in numerical stability, accuracy in long time computing and ability to preserve the invariants of the DP equation. 展开更多
关键词 DEGASPERIS-PROCESI EQUATION bi-Hamiltonian structure Structure-preserving SCHEME FOURIER PSEUDOSPECTRAL method
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