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Preparation and electrochemical properties of Sn/C composites

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Rare Metals 2019年第10期38卷 996-1002页

作者： Bei-ping Wang Rui Lv dong-Sheng Lan School of Materials Science and Engineering North Minzu UniversityYinchuan 750021China School of Materials Science and Engineering Sun Yat-Sen UniversityGuangzhou 510275China

The metal tin(Sn),as one potential anode material for lithium-ion batteries,rapidly.degrades its cy.lic performance due to huge volume expansion/contraction during lithium intercalation/de-intercalation *** carbon was adopted as conductive and buffer matrix to form Sn/C *** products were prepared by.hy.rothermal reaction and carbothermal reduction using tin tetrachloride and glucose as raw *** composites were characterized by.X-ray.diffraction(XRD),Raman spectroscopy.scanning electron microscopy.SEM),transmission electron microscopy.TEM),cy.lic voltammetry.CV) and galvanostatic charge/discharge *** results show that relative smaller metallic tin particles in 1:8 Sn/C composite are formed and distributed more uniformly.in the carbon *** lithium intercalation capacity.of Sn/C composites reaches 820.4 mAh·g-1,and the capacity.retention over 60 cy.les remains 54.1%.1:8 Sn/C composite exhibits enhanced rate performance and cy.lic stability.compared to1:5 and 1:10 samples.

关键词： Lithium-ion battery Tin/carbon composite Hy.rothermal method Electrochemical performance

Design of low-energy.transfer from lunar orbit to asteroid in the Sun-Earth-Moon sy.tem

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Acta Mechanica Sinica 2014年第6期30卷 966-972页

作者： y.-Min Wang dong Qiao ping-y.an Cui School of Aerospace Engineering Beijing Institute of Technology Key.Laboratory.of Dy.amics and Control of Flight Vehicle Ministry of Education

Asteroid exploration trajectories which start from a lunar orbit are investigated in this *** is assumed that the probe departs from lunar orbit and returns to the vicinity.of Earth,then escapes from the Earth by.performing a perigee maneuver.A low-energy.transfer in Sun-EarthMoon sy.tem is ***,the feasible region of lowenergy.transfer from lunar orbit to perigee within 5 000 km height above the Earth surface in Sun-Earth-Moon sy.tem is calculated and *** transfer ty.es are found,i.e.,large maneuver and fast transfers,small maneuver and fast transfers,and disordered and slow *** of feasibility.trajectories belong to the first two ***,the lowenergy.trajectory.leg from lunar orbit to perigee and a heliocentric trajectory.leg from perigee to asteroid are patched by.a perigee *** optimal full-transfer trajectory.is obtained by.exploiting the differential evolution ***,taking 4179 Toutatis asteroid as the target,some low-energy.transfer trajectories are obtained and analy.ed.

关键词： Lunar orbit Asteroid exploration Low-energy.transfer Sun-Earth-Moon sy.tem

Molecular Dy.amics Simulation of Glucomannan Solution

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Chinese Journal of Structural Chemistry 2005年第7期24卷 841-845,740页

作者： SUNy.-Jing GUANy.ng-Guang ZHUy.ng-dong TIANShi-ping CollegeofFoodSctence FujianAgricultureandForestryUniversityFuzhouFujian350002China CollegeofInformationandComputer FujianAgricultureandForestryUniversi~_FuzhouFujian350002China Key.aboratory.fPhotosy.thesisandEnvironmentalMolecularPhy.iology InstituteofBotanyTheChineseAcademyofSciencesBeijing100093China

The method of molecular dy.amics simulation is carried out to simulate the KGM segment in solution, investigate the stable conformation and compute its energy. and discuss the effect of the change of hy.rogen bond on its structure and energy. The results show that the structure of KGM segment can be optimized by.molecular simulation method and the most stable conformation can be found, indicating the hy.rogen bond is the main factor influencing the conformation and property.of KGM.

关键词： glucomannan conformation hy.rogen bond

Regulated polarization degree of upconversion luminescence and multiple anti-counterfeit applications

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Rare Metals 2024年第5期43卷 2172-2183页

作者： dong-ping Wen ping Chen y. Liang Xiao-Ming Mo Cao-Feng Pan Center On Nanoenergy.Research Guangxi Key Laboratory for Relativistic AstrophysicsSchool of Physical Science and TechnologyGuangxi UniversityNanning 530004China Key.Laboratory.of Micronano Energy.and Sensor CAS Center for Excellence in NanoscienceBeijing Institute of Nanoenergy and NanosystemsChinese Academy of SciencesBeijing 100140China

Polarization upconversion luminescence(PUCL)of lanthanide ions(Ln^(3+))has been widely.used in single particle tracking,microfluidics detection,three-dimensional display.,and so ***,no effective strategy.has been developed for modulating *** we report a strategy.to regulate PUCL in Ho^(3+)-doped Nay.4single nanorods based on the number of upconversion *** constructing a multiphoton upconversion sy.tem for Ho^(3+),we regulate the degree of polarization(DOP)of PUCL from 0.590 for two-photon luminescence to 0.929 for three-photon upconversion luminescence(UCL).Furthermore,our strategy.is verified from cross-relaxation between Ho^(3+)and y.^(3+),excitation wavelength,excitation power density.and local site *** this regulation strategy.of PUCL has also been achieved in Tm^(3+),with the DOP ranging from 0.233 for two-photon luminescence to 0.925 for four-photon UCL Besides,multi-dimensional anti-counterfeiting display.has been explored with *** work provides an effective strategy.for regulating PUCL and also provides more opportunities for the development of polarization display.optical encoding,anti-counterfeiting,and integrated optical devices.

关键词： Polarization upconversion luminescence Degree of polarization Population density.of excited state Number of upconversion photons Polarization anti-counterfeitingdisplay

RESEARCH ON THE CONDITION TO SET A TAILRACE SURGE TANK

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Journal of Hy.rody.amics 2004年第4期16卷 486-491页

作者： ZHAOGui-lian y.NGjian-dong XUy.an-jie LIJin-ping StateKey.aboratory.fWaterResourcesandHy.ropowerEngineeringScience WuhanUniversityWuhan430072China SchoolofCivilandArchitecturalEngineering WuhanUniversityWuhan430072China

When using the draft-tube vacuum to be less than 8.0 m as the rule to set atailrace surge tank, a mixing function that describes the process of water-hammer vacuum andvelocity.head vacuum varied with time is proposed, on the assumption that the guide vane of thehy.raulic turbine and the turbine discharge were all changed linearly. An exact maximum of thedraft-tube vacuum for the first-phase water-hammer and the last-phase water-hammer is *** a much more reasonable formula of critical tailrace length is derived. The results of twocases show that the formula proposed can determine correctly.and reasonably.whether a tail-racesurge tank is needed or not, and are more suitable for project design than the formula suggested by.he specification.

关键词： water-column separation tailrace surge tank critical tailrace length first-phase water hammer last-phase water hammer

Modeling sintering behavior of metal fibers with different fiber angles

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Rare Metals 2018年第10期37卷 886-893页

作者： dong-dong Chen Zhou-Shun Zheng Jian-Zhong Wang Hui-ping Tang School of Mathematics and Statistics Central South University State Key.Laboratory.of Porous Metal Materials Northwest Institute for Nonferrous Metal Research

The formation of sintering necks between two metal fibers was investigated using the oval-oval model with respect to the fiber angle range of 0°-90°. Surface diffusion was assumed to be the predominant mechanism in every.section of the junction of two metal fibers in this model, which was addressed numerically.using the level- set method. The growth rates of the sintering necks in the direction of the bisector of obtuse angle, the bisector of acute angle and the fiber axis were discussed in detail. It is found that the growth rate of the sintering necks decreases with fiber angle increasing in the direction of the fiber axis and the bisector of acute angle. However, an opposite variation in growth rate of sintering necks can be found in the direction of the bisector of obtuse angle. The numerical simulation results show that the growth rate of the sintering necks is significantly.affected by.the initial local geomet- rical structure which is determined by.the fiber angle.

关键词： Metal fiber Surface diffusion Fiber angle Initial local geometrical structure Initial evolution speed

High-dose dexamethasone regulates microglial polarization via the GR/JAK1/STAT3 signaling pathway.after traumatic brain injury

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Neural Regeneration Research 2025年第9期20卷 2611-2623页

作者： Mengshi y.ng Miao Bai y.an Zhuang Shenghua Lu Qianqian Ge Hao Li y. Deng Hongbin Wu Xiaojian Xu Fei Niu Xinlong dong Bin Zhang Baiy.n Liu Beijing Tiantan Hospital Capital Medical UniversityBeijingChina Department of Neurology The First Hospital of Tsinghua UniversityBeijingChina Department of Neurotrauma and Beijing Key.Laboratory.of Central Nervous Sy.tem Injury Beijing Neurosurgical InstituteCapital Medical UniversityBeijingChina Department of Critical Care Medicine Beijing Tiantan HospitalCapital Medical UniversityBeijingChina Center for Nerve Injury.and Repair Beijing Institute of Brain DisordersChina National Clinical Research Center for Neurological DiseasesBeijingChina

Although microglial polarization and neuroinflammation are crucial cellular responses after traumatic brain injury.the fundamental regulatory.and functional mechanisms remain insufficiently.*** potent anti-inflammato ry.agents,the use of glucoco rticoids in traumatic brain injury.is still controversial,and their regulatory.effects on microglial polarization are not y.t *** the present study.we sought to determine whether exacerbation of traumatic brain injury.caused by.high-dose dexamethasone is related to its regulatory.effects on microglial polarization and its mechanisms of *** vitro cultured BV2 cells and primary.microglia and a controlled cortical impact mouse model were used to investigate the effects of dexamethasone on microglial ***,dexamethasone,RU486(a glucocorticoid receptor antagonist),and ruxolitinib(a Janus kinase 1 antagonist)were ***-sequencing data obtained from a C57BL/6 mouse model of traumatic brain injury.were used to identify.potential targets of *** Morris water maze,quantitative reverse transcription-poly.erase chain reaction,western blotting,immunofluorescence and confocal microscopy.analy.is,and TUNEL,Nissl,and Golgi staining were performed to investigate our ***-throughput sequencing results showed that arginase 1,a marker of M2 microglia,was significantly.downregulated in the dexamethasone group compared with the traumatic brain injury.group at3 day. post-traumatic brain *** dexamethasone inhibited M1 and M2 microglia,with a more pronounced inhibitory.effect on M2microglia in vitro and in *** receptor play. an indispensable role in microglial polarization after dexamethasone treatment following traumatic brain ***,glucocorticoid receptor activation increased the number of apoptotic cells and neuronal death,and also decreased the density.of dendritic spines.A possible downstream receptor signaling mechanism is th

关键词： apoptosis BV2 microglia dexamethasone glucocorticoid receptor glucocorticoids innate immune sy.tem microglial polarization neuroinflammation primary.microglia traumatic brain injury

Seismic response analy.is of damper-connected adjacent structures with stochastic parameters

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Journal of Zhejiang University.Science A(Applied Phy.ics & Engineering) 2010年第6期11卷 402-414页

作者： dong-dong GE Hong-ping ZHU Dan-sheng WANG Min-shui HUANG School of Civil Engineering and Mechanics Huazhong University of Seience and Technology Wuhan 430074 China Hubei Key.Laboratory.of Control Structure Huazhong University of Science and Technology Wuhan 430074 China Transportation Research Center Wuhan Institute of Technology Wuhan 430073 China

Dy.amic response analy.is of damper connected adjacent multi-story.structures with uncertain parameters is carried out.A formula of the multi degree of freedom(MDOF) for the structure-damper sy.tem with stochastic parameters is *** uncertainties of mass and stiffness are taken into consideration *** ground acceleration is represented by.Kanai-Tajimi filtered non-stationary.*** mean square random responses of structural displacement and story.drift are chosen as the optimization *** variations of mean square responses of top floor displacements and bottom story.drifts in neighboring structures with the damper stiffness and damping coefficient are analy.ed in *** the parametric study.the acquiring optimum parameters of damper are regarded as numerical ***,a reducing order model of the MDOF sy.tem for adjacent structures with mean parameters is *** explicit expressions for determining optimal parameters of Kelvin model-defined damper which is used to connect adjacent single degree of freedom(SDOF) structures subjected to a white-noise excitation are employ.d to achieve the appropriate damper parameters,which are called theory.*** a comparative study.it can be found that the theory.values of damper parameters are consistent with the results based on extensive parametric *** analy.ical results can be obtained by.using the first natural frequencies and the total mass of the adjacent deterministic structures with mean *** analy.ical formulas can be used to find appropriate parameters of damper between adjacent structures for engineering *** performance of damper is investigated on the basis of mitigations of mean square random responses of inter-story.drifts,displacements and accelerations in adjacent *** numerical results demonstrate the robustness of coupled building control strategies.

关键词： Adjacent structures Passive control Stochastic parameters Seismic response

Analy.ical Solution for the Transient Response of A Sloping Seabed Induced by.A P-Wave Line Source

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China Ocean Engineering 2023年第6期37卷 1044-1054页

作者： MA Rong SHAN Zhen-dong XIE Zhi-nan dong Rui JING Li-ping Key.Laboratory.of Earthquake Engineering and Engineering Vibration Institute of Engineering MechanicsChina Earthquake AdministrationHarbin 150080China Key.Laboratory.of Earthquake Disaster Mitigation Ministry of Emergency ManagementHarbin 150080China

Many.offshore marine structures are built on the seabed that are slightly.or considerably.*** study.the sloping seabed transient response during marine earthquakes,an analy.ical solution induced by.a P-wave line source embedded in the solid is *** the derivation,the wave fields in the fluid lay.r and the semi-infinite solid are firstly.constructed by.using the generalized ray.method and the fluid-solid interface reflection and transmission ***,the analy.ical solution in the transformed domain is obtained by.superposing these wave fields,and the analy.ical solution in the time domain by.apply.ng the analy.ical inverse Laplace transform *** the head wave generation conditions and arrival times at the fluid-solid interface are derived through this *** the use of numerical examples,the analy.ical solution is proved right and the impacts of the sloping angle on the hy.rody.amic pressure in the sea,the seismic wave propagation in the seabed,the head wave,and the Scholte wave at the seawater-seabed interface are also addressed.

关键词： marine earthquake seismic wave head wave Scholte wave sloping seabed