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Understanding the sluggish and highly variable transport kinetics of lithium ions in LiFePO_4

Science China Chemistry 2023年第11期66卷 3297-3306页

作者： Youcheng Hu Xiaoxiao Wang Peng Li Junxiang Chen shengli Chen Hubei Electrochemical Power Sources Key Laboratory Department of ChemistryWuhan UniversityWuhan 430072China CAS Key Laboratory of Design and Assembly of Functional Nanostructures Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China

LiFePO_(4),one of the mainstream cathode materials of current EV batteries,exhibits experimental diffusion coefficients(D_(c))of Li^(+)which are not only several orders of magnitude lower than those predicted by the ionic hopping barriers obtained from theoretical calculations and spectroscopic measurements,but also span several orders from 10^(-14)to 10^(-18)cm^(2)s^(-1)under different states of charge(SOC)and the charging rates(C-rates).Atomic level understanding of such sluggishness and diversity of Li^(+)transport kinetics would be of significance in improving the rate performance of LiFePO_(4)through material and operation optimization but remain ***,we show that the high sensitivity of Li^(+)hopping barriers on the local Li–Li coordination environments(numbers and configurations)plays a key role in the ion transport *** is due a neural network-based deep potential(DP)which allows accurate and efficient calculation of hopping barriers of Li^(+)in LiFePO_(4)with various Li–Li coordination environments,with which the kinetic Monte-Carlo(KMC)method was employed to determine the D_(c)values at various C-rates and SOC across a broad ***,an accelerated KMC simulation strategy is proposed to obtain the D_(c)values under a wide range of SOC at low C-rates,which agree well with that obtained from the galvanostatic intermittent titration technique(GITT).The present study provides accurate descriptions of Li^(+)transport kinetics at both very high and low C-rates,which remains challenging to experiments and first-principles calculations,***,it is revealed that the gradient distributions of Li^(+)density along the diffusion path result in great asymmetry in the barriers of the forward and backward hopping,causing very slow diffusion of Li^(+)and the diverse variation of D_(c).

关键词： lithium iron phosphate diffusion coefficient machine-learning potential kinetic Monte Carlo simulations

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Experimental evidence for seismic nucleation phase

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Chinese Science Bulletin 2002年第9期47卷 769-773页

作者： MA shengli MA Jin LIU Liqiang Institute of Geology&Laboratory of Tectonophysics China Seismol-ogical BureauBeijing 100029China

The friction experiments on macroscopically homogeneous and non-homogeneous faults were performed by using a double-shear friction rig, and the waveforms of acoustic emission and the fault slip corresponding to the stick-slip instability events were analyzed. The results indicate that there exist two types of nucleation phase for stick-slip instability of non-homogeneous faults, and one is coincident with the preslip model, the other with the cascade model. It is concluded that the seismic nucleation phase exists objectively, and its generation is related to heterogeneity of fault.

关键词： earthquake nucleation phase friction experiment acoustic emission fault slip.

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Development of a high-performance green Fe-Al_(2)O_(3)composites using Bayan Obo minerals:Enhancement effects of CeO_(2)

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Journal of Rare Earths 2023年第5期41卷 747-757,I0005页

作者： Yuxin Chen Ning Wang shengli An Changkun Cai Manyi Xie Xiwen Song School of Materials and Metallurgy Inner Mongolia University of Science and TechnologyBaotou 014010China Inner Mongolia Key Laboratory of Advanced Ceramic Materials and Devices Baotou 014010China Key Laboratory of Green Extraction&Efficient Utilization of Light Rare-Earth Resources Ministry of EducationBaotou 014010China

With the deepening understanding for the concept of sustainable development,the utilization of minerals is no longer limited to the traditional *** this study,an environment friendly method for preparing Fe-Al_(2)O_(3)composites by using natural minerals was ***,the effects of CeO_(2)on the properties of composites were *** mechanical properties of Fe-Al_(2)O_(3)composites prepared by natural minerals are affected by the brittleness of glass *** strength and toughness of the glass phase in the composite are improved successfully by using rare earth oxides,indicating that the natural rare earths in Bayan Obo minerals have an enhanced influence on the properties of composite *** results show that the properties of glass phase can be significantly improved by addition of CeO_(2).At the optimal addition of 3 wt%CeO_(2),the composite achieves the density of 4.21 g/cm^(3),flexural strength of 401 MPa,Vickers hardness of 13.07 GPa and fracture toughness of 6.58 MPa·m^(1/2).The composite has excellent mechanical properties,which can be used in engineering as a cheap structural *** study aims at reducing waste emissions,improving energy efficiencies and avoiding waste of rare earth resources during the preparation of composite materials.

关键词： Cleaner production Natural minerals Alumina matrix composites Energy saving Rare earth oxides

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Control Policy Learning Design for Vehicle Urban Positioning via BeiDou Navigation

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Journal of Systems Science & Complexity 2024年第1期37卷 114-135页

作者： QIN Yahang ZHANG Chengye CHEN Ci XIE shengli LEWIS Frank L School of Automation Guangdong University of TechnologyGuangzhou 510006China Guangdong Key Laboratory of IoT Information Technology Guangzhou 510006China. Center for Intelligent Batch Manufacturing Based on IoT Technology Key Laboratory of Intelligent Detection and The Internet of Things in Manufacturing Ministry of EducationGuangzhou 510006China Guangdong-HongKong-Macao Joint Laboratory for Smart discrete Manufacturing Guangzhou 510006China Key Laboratory of Intelligent Information Processing and System Integration of IoT Ministry of EducationGuangzhou 510006China. UTA Research Institute The University of Texas at ArlingtonFort WorthTX 76019USA

This paper presents a learning-based control policy design for point-to-point vehicle positioning in the urban environment via BeiDou *** navigating in urban canyons,the multipath effect is a kind of interference that causes the navigation signal to drift and thus imposes severe impacts on vehicle localization due to the reflection and diffraction of the BeiDou ***,the authors formulated the navigation control system with unknown vehicle dynamics into an optimal control-seeking problem through a linear discrete-time system,and the point-to-point localization control is modeled and handled by leveraging off-policy reinforcement learning for feedback *** proposed learning-based design guarantees optimality with prescribed performance and also stabilizes the closed-loop navigation system,without the full knowledge of the vehicle *** is seen that the proposed method can withstand the impact of the multipath effect while satisfying the prescribed convergence rate.A case study demonstrates that the proposed algorithms effectively drive the vehicle to a desired setpoint under the multipath effect introduced by actual experiments of BeiDou navigation in the urban environment.

关键词： BeiDou navigation multipath effect prescribed convergence rate reinforcement learning urban localization.

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Standard energies of combustion and standard enthalpies of formation for the complexes RE (Et_2dtc)_3(phen) (RE = Ho,Er,Tm,Yb,Lu)

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Rare Metals 2005年第4期24卷 301-305页

作者： WEI Qing CHEN Sanping YANG Xuwu GAO shengli SHI Qizhen Department of Chemistry Shaanxi Key Laboratory of Physico-Inorganic Chemistry Northwest University Xi＇an 710069 China

The treatment of ***2O （RE = Ho, Er, Tm, Yb, Lu; x = 3-4） with sodium diethyldithiocarbamate （NaEtEdtc-3H2O） and 1,10-phenanthroline hydrate （o-phen.H2O） in absolute ethanol yielded five ternary solid complexes RE（EtEdtC）a（phen）. IR spectra of the complexes showed that RE^3＋ coordinated to two sulfur atoms in NaEt2dtc and two nitrogen atoms in o-phen. The constant-volume energies of combustion of the complexes have been determined by a precise rotating-bomb calorimeter at 298.15 K. The standard enthalpies of combustion and standard enthalpies of formation were calculated.

关键词： thermochemistry combustion energy calorimeter RE(Et2dtc)3(phen) standard enthalpy of formation

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Rhinoplasty in China: A review of the most important events in its history of development

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Chinese Journal of Plastic and Reconstructive Surgery 2022年第4期4卷 149-153页

作者： shengli Li Qingfeng Li Department of Plastic and Reconstructive Surgery Shanghai Ninth People’s HospitalShanghai Jiao Tong University School of MedicineShanghai200011China

A review of the literature in commonly used retrieval systems generally yields minimal or no pertinent information on the early works of Chinese ***,the early works in rhinoplasty by pioneers *** Hu(胡懋廉)and *** Nyi(倪葆春)were retrieved from the database of Chinese Medical Journal published before1949 that overseas doctors could not gain access to online possibly due to the language barrier in collecting and processing those old professional data by main retrieval *** published original articles on costal cartilage applications for correction of saddle noses in as early as 1939 and 1949,respectively,which represent the earliest attempts of treating nasal deformities with costal cartilages in China as well as in *** private cosmetic surgical practices in rhinoplasty from the 1930s to the 1940s were recovered and briefly reviewed,and some of the most important clinical cases were *** important events related to rhinoplasty,such as the establishment of the first national society of rhinoplasty in Chengdu,China in 2011 and the successful performance of the first national congress on rhinoplasty in Shanghai,China in 2012,were included.

关键词： Rhinoplasty History Costal cartilage Society Congress

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Facile synthesis of defected TiO_(2-x)(B) nanosheet/graphene oxide hybrids with high photocatalytic H_(2) activity

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Journal of Materials Science & Technology 2021年第21期80卷 171-178页

作者： Xiangchen Kong Huiming Huang Zhaoyang Li Yanqin Liang Zhenguo Li shengli Zhu School of Materials Science and Engineering Tianjin UniversityTianjin300350China National Engineering Laboratory for Mobile Source Emission Control Technology China Automotive Technology&Research Center Co.Ltd.Tianjin300300China School of Materials Science and Engineering Lanzhou Jiaotong UniversityLanzhou730070China

TiO_(2)(B) nanosheets/GO(graphene oxide) hybrids are considered to be outstanding performance photocatalysts for high efficiency of H_(2) evolution. However, they still suffer severe challenges during the synthetic processes, such as a large amount of the capping agents adhering on the surface and easy occurrence of aggregation. To figure out these obstacles, Ar plasma treatment as a modified method in this study not only enable the TiO_(2)(B) nanosheets distributed uniformly on the GO sheets but also engineer defects within TiO_(2)(B) nanosheets to significantly improve the photocatalytic activity for the water splitting. The hydrogen evolution rate of the TiO_(2)-x(B)/GO sheets is 1.4 times higher compared with that of original TiO_(2)(B)/GO sheets without Ar plasma treatment. The improved photocatalytic properties were owing to the synergetic effects of oxygen vacancies and the heterojunction between GO and TiO_(2)(B), which can promote the visible light utilization and accelerate separation and transportation of photogenerated electron-holes. This study can provide a facile pathway to prepare the two-dimensional hybrid photocatalysts with high photocatalytic H_(2) activity.

关键词： TiO_(2)(B)nanosheets Plasma etching Structure defect Heterojunction Photocatalytic H_(2)evolution

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Research on Multi-Authority CP-ABE Access Control Model in Multicloud

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China Communications 2020年第8期17卷 220-233页

作者： shengli Zhou Guangxuan Chen Guangjie Huang Jin Shi Ting Kong Department of Computer and Information Security Zhejiang Police CollegeHangzhou 310053China Institute of Big-data and Network Security Zhejiang Police CollegeHangzhou 310053China Institute of Software Chinese Academy of SciencesBeijing 100190China

In order to solve the problems of data sharing security and policy conflict in multicloud storage systems(MCSS), this work designs an attribute mapping mechanism that extends ciphertext policy attribute-based encryption(CP-ABE), and proposes a multi-authority CP-ABE access control model that satisfies the need for multicloud storage access control. The mapping mechanism mainly involves the tree structure of CP-ABE and provides support for the types of attribute values. The framework and workflow of the model are described in detail. The effectiveness of the model is verified by building a simple prototype system, and the performance of the prototype system is analyzed. The results suggest that the proposed model is of theoretical and practical significance for access control research in MCSS. The CP-ABE has better performance in terms of computation time overhead than other models.

关键词： CP-ABE access control multicloud multi-authority trust

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Grain Size Effect of IrO_2 Nanocatalysts for the Oxygen Evolution Reaction

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Wuhan University Journal of Natural Sciences 2013年第4期18卷 289-294页

作者： HU Wei CHEN shengli College of Chemistry and Chemical Engineering Hubei University Hubei Key Laboratory of Electrochemical Power Sources College of Chemistry and Molecular Sciences Wuhan University

Combined with air annealing, rutile-structured IrO 2 nanoparticles with various sizes were prepared using colloidal method. The nanoparticles were used as the electrocatalysts for the oxygen evolution reaction （OER） in acidic media, and their grain size effect was studied. The results show that with the increase in annealing temperature, the grain size of the catalyst increases, and the voltammetric charges （the electroactive areas） and apparent activity for the OER decrease. The relationship between the intrinsic activity and the annealing temperature exhibits a volcano-type curve and the catalyst annealed at 550 ℃ achieved the best result.

关键词： acidic water electrolysis oxygen evolution reaction IrO 2 size effect voltammetric charges catalytic activity

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Laboratory acoustic emission study for earthquake generation process

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Earthquake Science 2014年第6期27卷 627-646页

作者： Xinglin Lei shengli Ma Geological Survey of Japan National Institute of Advanced Industrial Science and Technology (AIST) State Key Laboratory of Earthquake Dynamics Institute of Geology China Earthquake Administration

Since the similarity in size distribution of earthquakes and acoustic emissions （AE） was found in the 1960s, many laboratory studies have been motivated by the need to provide tools for the prediction of mining failures and natural earthquakes. This paper aims, on the one hand, to draw an outline of laboratory AE studies in the last 50 years, which have addressed seismological problems. Topics include the power laws in which the similarity between AEs and earthquakes is involved and progress that has been made in AE technology and laboratory AE study. On the other hand, this study will highlight some key issues intensively discussed, especially in the last three decades, such as aspects related to the pre-failure damage evolution, fault nucleation and growth in brittle rocks and discuss factors governing these processes.

关键词： Acoustic emission (AE) Pre-failure damage Rock fracture Earthquake Fault nucleation Process zone

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