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Carbon nanotube directed three-dimensional porous Li2FeSiO4 composite for lithium batteries

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Nano Research 2017年第1期10卷 229-237页

作者： Wencong Wang haichen liang Ling Zhang Serguei V. Savilov Jiangfeng Ni liang Li College of Physics Optoelectronics and Energy Center for Energy Conversion Materials & Physics (CECMP) Collaborative Innovation Center of Suzhou Nano Science and Technology Soochow University Suzhou 215006 China Chemistry Department M.V. Lomonosov Moscow State University Moscow 119991 Russia

Lithium iron silicate （Li2FeSiO4） is capable of affording a much higher capacity than conventional cathodes, and thus, it shows great promise for high-energy battery applications. However, its capacity has often been adversely affected by poor reaction activity due to the extremely low electronic and ionic conductivity of silicates. Here, we for the first time report on a rational engineering strategy towards a highly active Li2FeSiO4 by designing a carbon nanotube （CNT） directed three-dimensional （3D） porous Li2FeSiO4 composite. As the CNT framework enables rapid electron transport, and the rich pores allow efficient electrolyte penetration, this unique 3D Li2FeSiO4-CNT composite exhibits a high capacity of 214 mAh·g^-1 and retains 96% of this value over 40 cycles, thus, outstripping many previously reported Li2FeSiO4-based materials. Kinetic analysis reveals a high Li＋ diffusivity due to coupling of the migration of electrons and ions. This research highlights the potential for engineering 3D porous structure to construct highly efficient electrodes for battery applications.

关键词： lithium battery lithium iron silicate cathode electrochemicalperformance

Analysis and experimental study on resistance-increasing behavior of composite high efficiency autonomous inflow control device

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Petroleum Science 2024年第2期21卷 1290-1304页

作者： liang-liang Dong Yu-Lin Zhang School of Mechatronic Engineering Southwest Petroleum UniversityChengdu610500SichuanChina State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum UniversityChengdu610500SichuanChina Oil and Gas Equipment Technology Sharing and Service Platform of Sichuan ProvinceChengdu610500SichuanChina

Bottom water coning is the main reason to reduce the recovery of horizontal bottom water reservoir. By water coning, we mean the oil-water interface changes from a horizontal state to a mound-shaped cone and breaks through to the wellbore. Autonomous inflow control device(AICD) is an important instrument maintain normal production after bottom water coning, however, the resistance increasing ability of the swirl type AICD is insufficient at present, which seriously affects the water control effect. Aiming this problem, this paper designs a multi-stage resistance-increasing and composite type AICD. The separation mechanism of oil-water two phases in this structure, the resistance form of oil-water single phase and the resistance-increasing principle of water phase are analyzed. Establishing the dual-phase multi-stage separation and resistance-increasing model, and verified by measuring the throttling pressure drop and oil-water volume fraction of the AICD, it is found that the composite type AICD has the effect of ICD and AICD at the same time, which can balance the production rate of each well section at the initial stage of production, delay the occurrence of bottom water coning. In the middle and later stages of production, water-blocking can be effectively increased to achieve water control and stable *** structural sensitivity analysis, the influence law of various structural parameters on the water control performance of composite AICD was obtained. The simulation calculation results show that,compared with the existing swirl type AICD, composite AICD has higher sensitivity to moisture content,the water phase throttling pressure drop is increased by 4.5 times on average. The composite AICD is suitable for the entire stage of horizontal well production.

关键词： Water control Flow separation Flow resistance-increasing AICD device Simulation and experiment

Global existence and large-time behavior for primitive equations with the free boundary

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Science China Mathematics 2024年第10期67卷 2303-2330页

作者： Hai-liang Li Chuangchuang liang School of Mathematical Sciences Capital Normal UniversityBeijing 100048China Academy for Multidisciplinary Studies Capital Normal UniversityBeijing 100048China College of Mathematics and Statistics Chongqing UniversityChongqing 401331China

In the present paper, the primitive equations, which can be used to simulate the large-scale motion of the ocean and atmosphere, are considered in the three-dimensional domain bounded below by a fixed solid boundary and above by a free-moving boundary. The global existence and uniqueness of strong solutions are established, and the long-time convergence to the equilibrium state is shown to be either at an exponential rate for the horizontal periodic domain or at an algebraic rate for the horizontal whole space.

关键词： primitive equations the free boundary value problem global well-posedness large-time behavior

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Sufficient Conditions for Amalgamated 3-Manifolds to be ∂-Irreducible

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Chinese Annals of Mathematics,Series B 2024年第2期45卷 161-172页

作者： Bing FANG Fengchun LEI liang liang School of Mathematical Sciences Dalian University of TechnologyDalian 116024LiaoningChina School of Mathematics Liaoning Normal UniversityDalian 116029LiaoningChina

In this paper,the authors give some sufficient conditions for an amalgamated 3-manifold along a compact connected surface F with boundary to be ∂-irreducible in terms of distances between some kinds of vertex subsets ... 详细信息

关键词： ∂-Irreducibility Irreducibility Amalgamated 3-manifold Curve complex Arc complex

Towards net zero carbon buildings:Accounting the building embodied carbon and life cycle-based policy design for Greater Bay Area,China

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Geoscience Frontiers 2024年第3期15卷 284-297页

作者： Hanwei liang Xin Bian liang Dong Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters/Research Center of Urban Sustainable Development/School of Geographical Sciences Nanjing University of Information Science&Technology(NUIST)Nanjing 210044China Department of Architecture and Civil Engineering Chalmers University of TechnologySE-41296 GothenburgSweden Shenzhen Research Institute(SRI) City University of Hong KongShenzhenChina Department of Public and International Affairs(PIA) City University of Hong Kong999077Hong Kong Special Administrative Region School of Energy and Environment(SEE) City University of Hong Kong999077Hong Kong Special Administrative RegionChina Centre for Public Affairs and Law City University of Hong Kong999077Hong Kong Special Administrative RegionChina

Carbon mitigation of buildings is critical to promote a net-zero *** international society has vigorously promoted‘‘Net Zero Carbon Buildings”across the globe,and accounting for building carbon emissions is critical to support this *** carbon,which represents carbon emissions from the entire lifecycle of the buildings,is fundamental for realizing the idea of zero ***,only limited studies have been conducted so far that take into account the city *** paper aimed to act as a first try to account for the embodied carbon emissions in buildings in 2020 for the Guangdong-Hong Kong Macao Greater Bay Area in China(GBA).We integrated remote sensing techniques such as night-time light data(NLT)and building material flows analysis to calculate and spatialize the newly generated building material stocks(MS).Based on the MS data,we further applied life cycle assessment(LCA)to assess the embodied carbon in the *** results highlighted that over 163 million tons of embodied carbon in buildings of GBA are expected to be generated,from 497 million tons of newly generated building MS in *** embodied carbon in each life cycle stage is valuable for further lifecyclebased policy designs for:(i)supporting the updating of the green building certification system with consideration of the embodied carbon;(ii)promoting the green building material application and certification;and(iii)reducing the embodied carbon intensity from compact urban planning policy,such as the urban agglomeration policies in *** goal of this paper was to shed a light on reducing carbon emissions from the perspective of the entire lifecycle and promote the development of net zero carbon buildings in China and Asia-Pacific.

关键词： Net zero carbon building Embodied carbon Life cycle assessment Life cycle-based policies Greater Bay area

Reliability Assessment of a New General Matching Composed Network

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China Communications 2024年第2期21卷 245-257页

作者： Zhengyuan liang Junbin liang Guoxuan Zhong Guangxi Key Laboratory of Multimedia Communications and Network Technology School of ComputerElectronics and InformationGuangxi UniversityNanning 530004China Jiangxi Engineering Laboratory of IoT Technologies for Crop Growth Ji’an 343000China

The reliability of a network is an important indicator for maintaining communication and ensuring its stable operation. Therefore, the assessment of reliability in underlying interconnection networks has become an increasingly important research issue. However, at present, the reliability assessment of many interconnected networks is not yet accurate,which inevitably weakens their fault tolerance and diagnostic capabilities. To improve network reliability,researchers have proposed various methods and strategies for precise assessment. This paper introduces a novel family of interconnection networks called general matching composed networks(gMCNs), which is based on the common characteristics of network topology structure. After analyzing the topological properties of gMCNs, we establish a relationship between super connectivity and conditional diagnosability of gMCNs. Furthermore, we assess the reliability of g MCNs, and determine the conditional diagnosability of many interconnection networks.

关键词： conditional diagnosability interconnection networks network reliability super connectivity

赛艇运动员肋骨应力损伤机制、风险因素及防治研究

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中国体育科技 2024年第5期60卷 12-20页

作者：梁艺炜杨海晨福建师范大学福建福州350117

肋骨应力损伤(rib stress injury,RSI)是赛艇运动员报道最多、训练时间损失较长的伤病类型。围绕病因机制、风险因素及防治措施3个方面进行回顾与梳理,发现RSI与运动员躯干、四肢和肌肉骨骼的划桨生物力学存在关联,并提出涉及前锯肌、... 详细信息

肋骨应力损伤(rib stress injury,RSI)是赛艇运动员报道最多、训练时间损失较长的伤病类型。围绕病因机制、风险因素及防治措施3个方面进行回顾与梳理,发现RSI与运动员躯干、四肢和肌肉骨骼的划桨生物力学存在关联,并提出涉及前锯肌、腹外斜肌和肩关节牵开器作用的可能损伤机制。致伤病因的关键风险因素包括:内在因素(低骨密度、性别)、外在因素(训练负荷和运动水平、划桨技术、设备类型等)和其他可能性成因。基于此,提出针对性的风险预防及管理策略,并对已有损伤症状进行诊断决策和治疗康复。

关键词：赛艇肋骨应力损伤防治措施

Non-interactive SM2 threshold signature scheme with identifiable abort

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Frontiers of Computer Science 2024年第1期18卷 171-185页

作者： Huiqiang liang Jianhua CHEN School of Mathematics and Statistics Wuhan UniversityWuhan 430072China

A threshold signature is a special digital signature in which the N-signer share the private key x and can construct a valid signature for any subset of the included t-signer,but less than t-signer cannot obtain any *** the breakthrough achievements of threshold ECDSA signature and threshold Schnorr signature,the existing threshold SM2 signature is still limited to two parties or based on the honest majority setting,there is no more effective solution for the multiparty *** make the SM2 signature have more flexible application scenarios,promote the application of the SM2 signature scheme in the blockchain system and secure cryptocurrency *** paper designs a non-interactive threshold SM2signature schemebasedon partially homomorphic encryption and zero-knowledge *** the last round requires the message input,so make our scheme non-interactive,and the pre-signing process takes 2 rounds of communication to complete after the key *** allow arbitrary threshold t

关键词： SM2 signature secure multi-party computation threshold signature UC-secure dishonest majority

Geometrical transition properties of vortex cavitation and associated flow-choking characteristics in poppet valves

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第6期25卷 455-469页

作者： liang LU Zhongdong liang Yuming LIU Zhipeng WANG Shohei RYU School of Mechanical Engineering Tongji UniversityShanghai 201804China Frontiers Science Center for Intelligent Autonomous Systems Tongji UniversityShanghai 201210China Technical Research Laboratory Hitachi Construction Machinery Co.Ltd.Tsuchiura 300-0013Japan

Poppet valves have become increasingly significant in ensuring precise digital flow rate and pressure control in hydraulic systems,necessitating a more profound understanding of the geometrical properties of cavitation in them,as well as associated flow-choking *** a comparative analysis with experimentally observed cavity images,we found that large eddy simulation(LES)turbulence modeling effectively replicates the geometrical properties of cavitation in these *** analysis demonstrated that cavitation is generated from vortices that result from the interaction between the notch contracta flow and the surrounding fluid *** in the internal or external vena contracta conditions result in fixed or discrete cavities,and the length-to-diameter ratio serves as a measure of the transition between internal and external vena contracta flow *** study establishes a threshold length-to-diameter ratio of approximately 2 for the tested poppet *** specifically,in notch structures with a smaller valve opening,longer sealing length,and smaller throttling angle(corresponding to a larger length-to-diameter ratio),the liquid-to-vapor transfer process is more evident than that in the reverse direction.A long-standing vapor cavity becomes fixed inside the notch,leading to a more pronounced flow-choking *** contrast,for structures with a smaller length-to-diameter ratio,the cavitation process for discrete vapor cavities is more complete,ensuring fluid flow continuity and significantly reducing the occurrence of the flow-choking phenomenon.

关键词： Poppet valves Vena contracta Vortex flow Vapor cavity Flow-choking