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An intermittent lithium deposition model based on CuMnbimetallic MOF derivatives for composite lithium anode with ultrahigh areal capacity and current densities

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Nano Research 2024年第4期17卷 2763-2769页

作者： Tao Wei Yanyan Zhou Cheng Sun Xingtong guo Shoudong Xu Daifen Chen Yongfu tang school of Energy and Power Jiangsu University of Science and TechnologyZhenjiang 212003China State Key Laboratory of Metastable Materials Science and Technology(MMST) Hebei Key Laboratory of Applied ChemistryYanshan UniversityQinhuangdao 066004China College of Materials Science and Engineering Taiyuan University of TechnologyTaiyuan 030024China

Recently,three-dimensional(3.)conductive frameworks have been chosen as the host for composite lithium(Li)metal anode because of their exceptional electrical conductivity and remarkable thermal and electrochemical ***,Li tends to accumulate on the top of the 3. frameworks with homogenous lithiophilicity and Li dendrite still *** work firstly designed a bimetallic metal-organic framework(MOF)(CuMn-MOF)derived Cu_(2.O and Mn_(3.O_(4) nanoparticles decorated carbon cloth(CC)substrates(CC@Cu_(2.O/Mn_(3.O_(4))to fabricate a composite Li *** to the synergistic effects of lithiophilic Cu_(2.O and Mn_(3.O_(4),the CC@Cu_(2.O/Mn_(3.O_(4)@Li symmetrical cell can afford a prolonged cycling lifespan(1400 h)under an ultrahigh current density and areal capacity(6 mA·cm^(-2./6 mAh·cm^(-2.).When coupled with the LiFePO_(4)(LFP)cathode,the LFP||CC@Cu_(2.O/Mn_(3.O_(4)@Li full cell demonstrated a superior performance of 89.7 mAh·g^(-1) even at an extremely high current density(10 C).Furthermore,it can also be matched well with LiNi_(0.5)Co^(0).2.n_(0.3.O_(2.(NCM52.)***,to explain the excellent performances of the CC@Cu_(2.O/Mn_(3.O_(4)@Li composite anode,an intermittent model was also *** study offers a novel model that can enhance our comprehension of the Li deposition behavior and pave the way to attain stable and safe Li metal anodes by employing bimetallic MOF-derived materials to construct 3. frameworks.

关键词： lithium metal anode(LMA) three-dimensional(3.)frameworks intermittent lithiophilic model high areal capacity bimetallic metal-organic frameworks(MOFs)

Quasi-secure quantum dialogue using single photons

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Science china(Physics,Mechanics & Astronomy) 2007年第5期50卷 558-562页

作者： YANG YuGuang1,2.& WEN QiaoYan3. College of Computer Science and Technology, beijing university of Technology, beijing 10002., china 2.State Key Laboratory of Information Security, Graduate university of the Chinese Academy of sciences, beijing 100049, china 3.school of Science, beijing university of Posts and Telecommunications, beijing 100876, china College of Computer Science and Technology Beijing University of Technology Beijing China State Key Laboratory of Information Security Graduate University of the Chinese Academy of Sciences Beijing China school of Science Beijing University of Posts and Telecommunications Beijing China

A quasi-secure quantum dialogue protocol using single photons was proposed. Different from the previous entanglement-based protocols, the present protocol uses batches of single photons which run back and forth between the two parties. A round run for each photon makes the two parties each obtain a classical bit of information. So the efficiency of information transmission can be increased. The present scheme is practical and well within the present-day technology.

关键词： quantum dialogue, single photon, quantum secure direct communication

OBLIQUE DERIVATIVE PROBLEMS FOR SECOND ORDER NONLINEAR MIXED EQUATIONS WITH DEGENERATE LINE

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Acta Mathematica Scientia 2008年第3期28卷 604-612页

作者：闻国椿 school of mathematical {2. Peking University

The present article deals with oblique derivative problems for some nonlinear mixed equations with parabolic degeneracy, which include the Tricomi problem as a special case. First, the formulation of the problems for the equations is given; next, the representation and estimates of solutions for the above problems are obtained; finally, the existence of solutions for the problems is proved by the successive iteration and the compactness principle of solutions of the problems. In this article, the author uses the complex method, namely, the complex functions in the elliptic domain and the hyperbolic complex functions in hyperbolic domain are used.

关键词： Oblique derivative problems nonlinear mixed equations parabolic degeneracy

Some basic concepts and problems on the petrogenesis of intra-plate ocean island basalts

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Chinese Science Bulletin 2009年第22期54卷 4148-4160页

作者： NIU Yaoling1,2.3.1 Department of Earth sciences, Durham university, Durham DH1 3.E, UK 2.{2. of Earth sciences and Resources, china university of Geosciences, beijing 100083. china 3.{2. of Earth and Space sciences, Peking university, beijing 100871, china Department of Earth sciences Durham University Durham UK school of Earth sciences and Resources China University of Geosciences Beijing China school of Earth and Space sciences Peking University Beijing China

Basaltic magmatism that builds intra-plate ocean islands is often considered to be genetically associated with "hotspots" or "mantle plumes". While there have been many discussions on why ocean island basalts (OIB) are geochemically highly enriched as an integral part of the mantle plume hypothesis, our current understanding on the origin of OIB source material remains unsatisfactory, and some prevailing ideas need revision. One of the most popular views states that OIB source material is recycled oceanic crust (ROC). Among many problems with the ROC model, the ocean crust is simply too depleted (e.g., [La/Sm]PM > 1) OIB. Another popular view states that the enriched component of OIB comes from recycled continental crust (RCC, i.e.; terrigenous sediments). While both CC and OIB are enriched in many incompatible elements (e.g., both have [La/Sm]PM >>1), the CC has characteristic enrichment in Pb and deletion in Nb, Ta, P and Ti. Such signature is too strong to be eliminated such that CC is unsuitable as source material for OIB. Plate tectonics and mantle circulation permit the presence of ROC and RCC materials in mantle source regions of basalts, but they must be volumetrically insignificant in contributing to basalt magmatism. The observation that OIB are not only enriched in incompatible elements, but also enriched in the progressively more incompatible elements indicates that the enriched component of OIB is of magmatic origin and most likely associated with low-degree melt metasomatism. H2. and CO2.rich incipient melt may form in the seismic low velocity zone (LVZ). This melt will rise because of buoyancy and concentrate into a melt rich layer atop the LVZ to metasomatize the growing lithosphere, forming the metasomatic vein lithologies. Erupted OIB melts may have three components: (1) fertile OIB source material from depth that is dominant, (2. the melt layer, and (3. assimilation of the metasomatic

关键词：岩石成因论海洋 OIB 矿物学

Comparative study on CO_2.corrosion behavior of N80,P110,X52.and 13.r pipe lines in simulated stratum water

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Science china(Technological sciences) 2010年第9期53卷 2342-2349页

作者： CAI YiDong1,guo PengChao1,LIU DaMeng1,CHEN ShiYu2.& LIU JunLai3.1 school of Energy Resources,{2. university of Geosciences,beijing 100083.{2. 2.school of Materials Science and Engineering,university of Science and Technology beijing,beijing 100083.{2. 3.school of Earth sciences and Resources,{2. university of Geosciences,beijing 100083.{2. school of Energy Resources China University of Geosciences Beijing China school of Materials Science and Engineering University of Science and Technology Beijing Beijing China school of Earth sciences and Resources China University of Geosciences Beijing China

To better understand the carbon dioxide (CO2. corrosion behavior of carbon steel and its influence on petroleum development (including drilling,production and transportation) in the Daqing Oilfield,CO2.corrosion behaviors of N80,P110,X52.and 13.r pipe lines in simulated solution at high temperature and high pressure condition are investigated by dynamic corrosion experiments,scanning electron microscope (SEM) and energy dispersive X-ray spectroscopy (EDS) *** show that the corrosion rate of all pipe lines increases quickly when CO2.partial pressure increases from 0.5 to 1.5 MPa,but it slows down when CO2.partial pressure further increases from 1.5 to 4.5 MPa,during which localized corrosion is *** the experimental temperature ranges from 60 to 12.°C,localized corrosion *** corrosion rate of all pipe lines decreases sharply when the temperature changes from 60 to 100°C,and it becomes stable after the temperature is higher than 100°*** the flow rate is in the range of 0–1.5 m/s,the corrosion rate of sample X52.remains unchanged,but localized corrosion gradually becomes very serious when the flow rate further *** analyzing the corrosion product scales of sample 13.r,some remarkable phenomena are *** the temperature range of 60–100°C,the corrosion product scales are loose and thick,but become very compact when the temperature increases above 100°*** the later case,localized corrosion is *** main components of the corrosion product scales are FeCO3.and Cr2.3.

关键词： CO2 corrosion pipe lines weight loss SEM EDS

SOME BOUNDARY VALUE PROBLEMS FOR NONLINEAR DEGENERATE ELLIPTIC EQUATIONS OF SECOND ORDER

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Acta Mathematica Scientia 2007年第3期27卷 663-672页

作者：闻国椿 school of mathematical {2. Peking University

The present article deals with some boundary value problems for nonlinear elliptic equations with degenerate rank 0 including the oblique derivative problem. Firstly the formulation and estimates of solutions of the oblique derivative problem are given, and then by the above estimates and the method of parameter extension, the existence of solutions of the above problem is proved. In this article, the complex analytic method is used, namely the corresponding problem for degenerate elliptic complex equations of first order is firstly discussed, afterwards the above problem for the degenerate elliptic equations of second order is solved.

关键词： Boundary value problems nonlinear elliptic equations parabolic degeneracy

The lifting scheme of 4-channel orthogonal wavelet transforms

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Progress in Natural Science:Materials International 2006年第1期16卷 100-104页

作者： PENG Lizhong and CHU Xiaoyong (LMAM, school of mathematical {2., Peking {3., beijing 100871, china) LMAM School of Mathematical Sciences Peking University Beijing 100871 China

The 4-channel smooth wavelets with linear phase and orthogonality are designed from the 2.channel orthogonal wavelets with high transfer vanishing moments. Reversely, for simple lifting scheme of such 4-channel orthogonal wavelet transforms, a new 2.channel orthogonal wavelet associated with this 4-channel wavelet is constructed. The new 2.channel wavelet has at least the same number of vanishing moments as the associated 4-channel one. Finally, by combining the two such 2.channel wavelet systems, the lifting scheme of 4-channel orthogonal wavelet transform, which has simple structure and is easy to apply, is presented.

关键词： lifting scheme 4-channel orthogonal wavelet 2.channel orthogonal wavelet vanishing moment transfer vanishing moment linear phase.

A new method of discovering new meteor showers from the IMO single-station video meteor database

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Science china(Physics,Mechanics & Astronomy) 2008年第8期51卷 1170-1178页

作者： LI Jun1,2.& ZHU Jin3.1 No.2.Middle school of {3.,{3. 100010,china 2.school of Journalism and Communication,Tsinghua university,{3. 100084,china 3.{3. Planterium,{3. 100044,china No.2.Middle school of beijing Beijing China school of Journalism and Communication Tsinghua University Beijing China beijing Planterium Beijing China

It has been found that unknown meteor showers could be efficiently discovered from the single station video meteor database of the International Meteor Organization(IMO) by assuming the geocentric velocity and adjusting it within the dynamically permitted range. The mean geocentric velocities of new meteor showers can be obtained,as well as the coordinates of the radiants. The activity period and maximum time can also be obtained if there are sufficient shower meteors. All single station video meteor observations between February 13.and 17(from 2.00 to 2.05) in IMO's database are processed with this method. As a result,two new meteor showers,one near RA=2.5.10°,Dec=41.82. in Hercules and the other near RA=2.3.03.,Dec=17.04° in Serpenids,are discovered. Some dynamical characteristics of the new meteor showers are also determined. Considering the random nature on the selection of period in this work,it is expected that there are some more potential new meteor showers in IMO's video database.

关键词： single-station video meteor database the process of single-station video meteor database discovery of new meteor showers

Analysis for twinning and slip in face-centered cubic crystals under axisymmetric co-deformation

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Science china(Technological sciences) 2006年第5期49卷 521-536页

作者： CHEN Zhiyong1,2. CAI Hongnian1, ZHANG Xinming2. WANG Fuchi1 & TAN Chengwen1,3.1. school of Material Science and Engineering, {3. Institute of Technology, {3. 100081, china 2. school of Material Science and Engineering, Central South university, Changsha 410083. china 3. school of Material Science and Engineering, {3. university of Aeronautics and Astronautics, {3. 100083. china school of Material Science and Engineering Beijing Institute of Technology Beijing China school of Material Science and Engineering Central South University Changsha China school of Material Science and Engineering Beijing University of Aeronautics and Astronautics Beijing China

The maximum work principle of Bishop-Hill was developed to analyze the axisymmetric co-deformation in face-centered cubic crystals (f.c.c.) for twinning on {111} 112.and slip on {111} 110 systems. The influence of ξ , the ratio of critical re- solved shear stress for twinning to slip, on the yield stress states and corresponding active slip or/and twinning systems for orientations in the standard stereographic triangle of cubic crystal was investigated systematically. The Taylor factors and the anisotropy of yield strength for three important orientations [100], [110] and [111] in orientation space were analyzed. It is found that the yield strength asymmetry for the case of axisymmetric de- formation of tension and compression can be explained based on the microscopic theory of crystal plasticity. The concept of orientation factor for twinning ability was proposed and the deformation mechanism map in the orientation space was established for the case of axisymmetric deformation. The deformation texture formation and development of f.c.c. crystals with low stacking fault energy for axisymmetric tension can be explained qualita- tively on the basis of analyzed results.

关键词： twinning slip face-centered cubic crystals axisymmetric co-deformation Bishop-Hill maximum work principle yield strength anisotropy