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Communications in Theoretical Physics 2023年第8期75卷 156-162页

作者： K W Shen q chen College of Physics and Mechanical&Electrical Engineering Jishou UniversityJishou 416000China School of Computational Science and Electronics Hunan Institute of EngineeringXiangtan 411104China

We investigate the topological properties of an antiferromagnetic(AFM)chain with an on-site periodic potential,considering the intrinsic spin–orbit coupling and an external Zeeman field along with the *** results indicate that Majorana zero modes(MZMs)can be observed by adjusting the strength of the periodic *** have calculated the energy spectrum,the wave-function and transport properties,and all these results support the existence of MZMs in the AFM ***,multiple topological phase transitions occur as the strength of the periodic potential changes,and several regions support MZMs.

关键词： AFM chain Majorana zero modes topological phase transitions periodic potential

Synthesis and mesomorphic properties of n-butyl-4- [4-((4-n-alkoxyl-tetrafluorophenyl)ethynyl)benzyloxy]benzoates

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Chinese Journal of Chemistry 1995年第6期13卷 515-519页

作者： Wen, JX Yin, HY chen, q CHINESE ACAD SCI SHANGHAI INST ORGAN CHEMSHANGHAI 200032PEOPLES R CHINA

A homologous series of n-butyl-4-[4-((4-n-alkoxyl-tetrafluorophenyl)ethynyl)benzyloxy] benzoates have been synthesized. Their phase transition temperatures have also measured by polarizing textural observation and con... 详细信息

关键词： liquid crystal synthesis mesomorphic properties

When joggers meet robots:the past,present,and future of research on humanoid robots

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Bio-Design and Manufacturing 2019年第2期2卷 108-118页

作者： George H.Z.Liu Michael Z.q.chen Yonghua chen Department of Mechanical Engineering The University of Hong KongPokfulamHong KongPeople’s Republic of China School of Automation Nanjing University of Science and TechnologyNanjing 210094JiangsuPeople’s Republic of China

Spawned by fast-paced progress in new materials and integrate circuit technology,the past two decades have witnessed tremendous development of humanoid robots for both scientific and commercial purposes,*** response and daily life *** the root of this trend are the increasing research interests and cooperation opportunities across different laboratories and *** application-driven requirements of high effectiveness and reliability of humanoid robots led intensive research and development in humanoid locomotion and control *** spite of the progress in the area,challenges such as unnatural locomotion control,inefficient multi-motion planning,and relatively slow disturbances recovery set further requirements for the next generation of humanoid ***,the purpose of this work is to review the current development of highly representative bipedal humanoid robots and discuss the potential to move the ideas and models forward from laboratory settings into the real *** this end,we also review the current clinical understanding of the walking and running dynamics to make the robot more human-like.

关键词： Humanoid robot Walking dynamics Dynamic control Bio-inspired gait Robot efficiency Shock absorption

NASH Drug Development:Seeing the Light at the End of the Tunnel?

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Journal of Clinical and Translational Hepatology 2023年第6期11卷 1397-1403页

作者： Yong q.chen Wuxi School of Medicine Jiangnan University Medical CenterWuxiJiangsuChina

Nonalcoholic steatohepatitis(NASH)is a chronic liver disease affecting a large population *** clinically approved drugs are *** this minireview,we discuss the heterogeneous nature of NASH and lack of consensus in outcome measures among clinical *** summarize NASH therapeutic targets and candidate *** compare the efficacy of 33 published clinical trials that evaluated noninvasive biomarkers and liver ***,phase Ⅱ trial results of fibroblast growth factor 21(FGF21)and phase Ⅲ trial results of resmetirom and pioglitazone are encouraging.

关键词： Nonalcoholic fatty liver disease Nonalcoholic steatohepatitis Fibroblast growth factor 21

An efficient SPH methodology for modelling mechanical characteristics of particulate composites

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Defence Technology（防务技术） 2021年第1期17卷 135-146页

作者： Z.J.Zheng S.Kulasegaram P.chen Y.q.chen Department of Mechanics College of Mechanical EngineeringChongqing University of TechnologyChongqing400054China Institute of Applied and Computational Mechanics Cardiff School of EngineeringCardiff UniversityQueen’s BuildingsThe ParadeCardiffCF243AAWalesUK Department of Mechanics and Engineering Science College of EngineeringPeking UniversityBeijing100871China

Particulate composites are one of the widely used materials in producing numerous state-of-the-art components in biomedical,automobile,aerospace including defence *** of modelling techniques have been adopted in the past to model mechanical behaviour of particulate *** to their favourable properties,particle-based methods provide a convenient platform to model failure or fracture of these *** particle hydrodynamics(SPH)is one of such methods which demonstrate excellent potential for modelling failure or fracture of particulate composites in a Lagrangian *** of the major challenges in using SPH method for modelling composite materials depends on accurate and efficient way to treat interface and boundary *** this paper,a masterslave method based multi-freedom constraints is proposed to impose essential boundary conditions and interfacial displacement constraints in modelling mechanical behaviour of composite materials using SPH *** proposed methodology enforces the above constraints more accurately and requires only smaller condition number for system stiffness matrix than the procedures based on typical penalty function approach.A minimum cut-off value-based error criteria is employed to improve the computational efficiency of the proposed *** addition,the proposed method is further enhanced by adopting a modified numerical interpolation scheme along the boundary to increase the accuracy and computational *** numerical examples demonstrate that the proposed master-slave approach yields better accuracy in enforcing displacement constraints and requires approximately the same computational time as that of penalty method.

关键词： Particulate composites SPH Essential boundary condition Multi-point constraints Master-slave method

Development of barium@alginate adsorbents for sulfate removal in lithium refining

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Frontiers of Chemical Science and Engineering 2021年第1期15卷 198-207页

作者： Lisa Xu Kaifei chen George q.chen Sandra E.Kentish Gang(Kevin)Li Department of Chemical Engineering The University of MelbourneParkvilleVIC 3010Australia

The demand for lithium has been steadily growing in recent years due to the boom of electric *** purity lithium is commonly used in the manufacture of battery grade lithium *** residuals originating from acid leaching of lithium ores must be limited to below 20 mg·L^(−1) during *** are methods to remove sulfate such as membrane processing and chemical precipitation using barium ***,membrane separation is unable to achieve the required purity while chemical precipitation often causes secondary contamination with barium and requires extra filtration processes that lead to increased processing *** this study,we developed a polymeric matrix entrapped with barium ions as a novel adsorbent to selectively adsorb sulfate in aqueous *** adsorbent was prepared by dropwise injection method where alginate droplets were crosslinked with barium to form hydrogel *** a typical scenario,the microcapsules had a diameter of 3 mm and contained 5 wt-%*** microcapsules could successfully reduce sulfate concentration in a solution from 100 to 16 mg·L^(−1),exceeding the removal ***,the microcapsules were mechanically unstable in the presence of an excess amount of ***,calcium ions were added as a secondary crosslinking agent to improve the integrity of the *** two-step Ca/Ba@alginate microcapsules showed an exceptional adsorption performance,reducing the sulfate concentration to as low as 0.02 mg·L^(−1).Since the sulfate selective microcapsules can be easily removed from the aqueous system and do not result in secondary barium contamination,these Ca/Ba@alginate adsorbents will find applications in ultra-refining of lithium in industry.

关键词： barium@alginate microcapsules dropwise injection sulfate removal lithium

On the mechanism of Si-promoted destabilization of TiC_(x)particles in Al alloys

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Journal of Materials Science & Technology 2023年第34期165卷 17-26页

作者： H.Dong Y.C.Guo Y.Z.chen F.Xia q.q.Guo q.chen G.L.Li J.Y.Zhao Y.Zhong J.P.Li School of Materials and Chemical Engineering Xi’an Technological UniversityXi’an 710021China State Key Lab.of Solidification Processing Northwestern Polytechnical UniversityXi’an 710072China School of Science Xi’an University of Science and TechnologyXi’an 710054China

TiC_(x)is an excellent composite strengthening particle and grain refiner for Al ***,the stability of TiC_(x)is poor when solute Si exists in Al alloy melts,which significantly depresses its strengthening and grain refining *** this work,the destabilization mechanisms of the TiC_(x)particles in Al-Si alloy melt with a composition of Al-7Si-7.5TiC were explored via experiments,first-principles calculations and thermodynamic *** experimental results show that Si atoms diffuse into TiC_(x)and Ti atoms are released into the Al melt to form a Ti-rich transition zone during the insulation of TiC_(x)in Al-Si melt,and the TiAlySiz and Al_(4)C_(3)phases are solidified in the Ti-rich zone and at Ti-rich zone/TiC_(x)interface,*** first principles calculations show that the low formation energy of C vacancies facilitates the rapid diffusion of Si atoms in TiC_(x),while the doping of Si atoms reduces the energy barrier of diffusion of Ti atoms in TiC_(x)and promotes the formation of Ti-rich *** thermodynamic calculations show that the wide crystallization temperature range of the destabilized product TiAlySiz phase is the key to continuous decomposition of TiC_(x)*** addition,the driving force of the main destabilization reaction of TiC_(x)in the Al-Si alloys is about 44 times higher than that in the Al alloys without Si *** indicates that the presence of solute Si remarkably promotes the subsequent decomposition process of TiC_(x)in the Al-Si alloy melts.

关键词： Al-Si alloy TiC_(x)particles Destabilization First principles calculations Thermodynamics

Passive structural control with inerters for a floating offshore wind turbine 36

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Passive structural control with inerters for a floating offs...

Simulation study on the effect of pre-evacuation time and exit width on evacuation

第36届中国控制会议

作者： Yinlong Hu Michael Z.q.chen College of Energy and Electrical Engineering Hohai University School of Automation Nanjing University of Science and Technology

ISBN: (纸本)9781538629185

This paper investigates an inerter-based passive structural control problem for a floating offshore wind turbine to reduce the loads induced by wind and *** proposed inerter-based system is composed of a passive spring,a damper,and a parallel-connected passive network.A parameter tuning method by maximizing the minimal modal damping of a linear design model is proposed,and the nonlinear wind turbine simulation code FAST-SC is *** simulations are conducted to show the effectiveness and the performance benefits of the proposed inerter-based structural control *** is shown that the proposed inerter-based system can effectively reduce the wind-and wave-induced loads compared with the conventional spring-damper system.

关键词： Inerter offshore wind turbine floating platform FAST inerter-based dynamic vibration absorber(IDVA)

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Chinese Science Bulletin 2006年第11期51卷 1381-1388页

作者： CHU Guanquan SUN Jinhua WANG q ingsong chen Sining State Key Laboratory of Fire Science University of Science and Technology of China Hefei 230026 China

Occupant pre-evacuation time is often oversimplified into an explicit value in evacuation calculation. In fact, it is not an explicit value but a random variable following some kind of probability distribution. In order to analyze the importance of pre-evacuation time in evacuation calculation, Grid- Flow evacuation model is utilized to study the effect of pre-evacuation time on evacuation under different occupant densities and exit widths in a single room scenario. The evacuation time calculated by using normal pre-evacuation distribution is compared with that calculated by explicit pre-evacuation time. Two faults are presented when pre-evacuation time is considered as an explicit value. The theory of con- gestion and queue is presented to analyze the cal- culation results. Moreover, this paper also presents probability distribution of the total evacuation time when the pre-evacuation time follows normal distri- bution. The results show that the evacuation time is dominated by pre-evacuation time and hardly de- pendent on occupant density when the mean pre- evacuation time is long. For long mean pre-evacua- tion time, low occupant density or wide exit, when pre-evacuation time follows normal distribution, the total evacuation time also follows normal distribution.

关键词：火灾预疏散时间正态分布出口宽度居住密度模拟研究

EVALUATION OF THE PROBABILITY DISTRIBUTION OF PITTING CORROSION FATIGUE LIFE IN AIRCRAFT MATERIALS

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Acta Mechanica Sinica 2003年第3期19卷 247-252页

作者：王清远 N.KAWAGOISHI q.chen R.M.PIDAPARTI Dept.of Civil Eng.and Mechanics Sichuan UniversityChengdu 610065China

Corrosion and fatigue properties of aircraft materials are known to have a considerable scatter due to the random nature of materials,loading,and environmental conditions.A probabilistic approach for predicting the pitting corrosion fatigue life has been investigated which captures the effect of the interaction of the cyclic load and corrosive environment and all stages of the corrosion fatigue process (*** pit nucleation and growth,pit-crack transition,short- and long-crack propagation).The probabilistic model investigated considers the uncertainties in the initial pit size,corrosion pitting current,and material properties due to the scatter found in the experimental *** Carlo simulations were performed to define the failure probability *** cumulative distribution functions of fatigue life agreed reasonably well with the existing experimental data.

关键词： pitting corrosion fatigue probabilistic modeling fatigue life prediction