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Genetic variation of Laminaria japonica (Phaeophyta) populations in China as revealed by RAPD markers

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Acta Oceanologica Sinica 2011年第2期30卷 103-112页

作者： BI Yanhui HU yuanjie ZHOU Zhigang Key Laboratory of Genetic Resources and Ecology in Aquaculture Aquaculture E-Institute ofShanghai Municipal Education Committee Shanghai Ocean University Shanghai 201306 China

For the population genetics analysis of the naturally grown brown seaweed Laminaria japonica （Laminariales,Phaeophyta） sampled from Dalian,Yantai,Weihai,Rongcheng and Qingdao in China,ten primers were employed to produce 88 bands as revealed by randomly amplified polymorphic DNA （RAPD） markers,and all these bands were *** to these band patterns,there were 94 distinct phenotypes occurred in 100 samples indicating the high heterozygosity of this *** population samples showed the highest percentage of polymorphism （71.67%）,and also the higher diversity estimated on the basis of the Shannon’s index （8.498）,suggesting that this population could be chosen as the best resource for genetic *** highest diversity of Yantai population possibly resulted from the introduction of *** used for interspecific cross breeding with *** cultivated in *** Dalian southwards to Qingdao,the genetic variation of the five populations became less with a decrease in latitude,possibly due to the natural selection especially of high *** genetic distance （Φ ST values） of the five populations was a little significantly correlated with the geographical distance （r=0.496） at P =0.05 by Mantel’s ***,Rongcheng and Yantai populations were closely grouped genetically together by Neighbor-joining cluster analysis probably in that the dispersal of the kelp by propagules more easily occurring in the range of relatively short *** analysis of molecular variance （AMOVA） also demonstrated that the relatively higher variation occurred among populations （71.49%） at an extremely significant level （P 0.000 1）.All these evidence showed that there was a relatively distinct genetic differentiation among the sampled kelp populations,and *** grown in China was also rather heterozygous in heredity.

关键词： AMOVA brown seaweed Laminaria japonica Aresch. population genetics RAPD genetic variation

Optical Trapping and Manipulation Using Optical Fibers

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Advanced Fiber Materials 2019年第2期1卷 83-100页

作者： Yuanhao Lou Dan Wu yuanjie Pang School of Optical and Electronic Information and Wuhan National Laboratory for Optoelectronics Huazhong University of Science and TechnologyWuhan430074HubeiChina

An optical trap forms a restoring optical force field to immobilize and manipulate tiny objects.A fiber optical trap is capable of establishing the restoring optical force field using one or a few pieces of optical fiber,and it greatly simplifies the optical setup by removing bulky optical components,such as microscope objectives from the working *** also inherits other major advantages of optical fibers:flexible in shape,robust against disturbance,and highly integrative with fiber-optic sys-tems and on-chip *** review will begin with a concise introduction on the principle of optical trapping techniques,followed by a comprehensive discussion on different types of fiber optical traps,including their structures,functionalities and associated fabrication techniques.A brief outlook to the future development and potential applications of fiber optical traps is given at the end.

关键词： Fiber optical traps Optical trapping Optical manipulation Optical fiber

Partially coherent vortex beams:Fundamentals and applications

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Science China(Physics,Mechanics & Astronomy) 2021年第2期64卷 32-50页

作者： Miao Dong ChengLiang Zhao YangJian Cai yuanjie Yang School of Physics University of Electronic Science and Technology of ChinaChengdu611731China School of Physical Science and Technology Soochow UniversitySuzhou215006China Shandong Provincial Engineering and Technical Centre of Light Manipulations&Shandong Provincial Key Laboratory of Optics and Photonic Device School of Physics and ElectronicsShandong Normal UniversityJinan250014China

It has been over 30 years since the concept of optical vortices was first proposed by Coullet et *** 1989,and the field of structured beams has grown *** the last two decades,partially coherent vortex beams(PCVBs)have received increasing interest in the fields of optical manipulation,optical communication,optical imaging,etc.,and great progress has been made in the area of the coherence singularities,generation methods,topological charge measurements,and promising applications of *** this review,we firstly outline the basic concepts of *** explicate the relationship between the coherence vortices and optical vortices,and the evolution behavior of optical vortices to coherence vortices is summarized in *** discuss a special form of coherence singularity,ring dislocation,mathematically and *** ring dislocation in the correlation functions under low coherence is dependent on the mode indices,which provide a feasible approach to measure mode indices of ***,we summarize the various methods for measuring the topological charge of PCVBs,highlight the measurement method based on the cross-correlation function,and a physical explanation on the relation between ring dislocation and topological charge is *** that,we review the recent advances on experimental generation of several kinds of ***,we give an overview on the potential applications of PCVBs.

关键词： coherence singularities coherence vortices vortex beams topological charge

An elastic model for bioinspired design of carbon nanotube bundles

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Acta Mechanica Sinica 2015年第2期31卷 205-215页

作者： Xiaoyu Sun Zuoqi Zhang yuanjie Xu Yongwei Zhang School of Civil Engineering Wuhan University Institute of High Performance Computing A*STARSingapore 138632Singapore

Collagen fibers provide a good example of making strong micro-or mesoscale fibers from nanoscale tropocollagen molecules through a staggered and crosslinked organization in a bottom-up *** the architectural features of collagen fibers has been shown to be a promising approach to develop carbon nanotube（CNT）fibers of high *** the present work,an elastic model is developed to describe the load transfer and failure propagation within the bioinspired CNT bundles,and to establish the relations of the mechanical properties of the bundles with a number of geometrical and physical parameters such as the CNT aspect ratio and longitudinal gap,interface cross-link density,and the functionalizationinduced degradation in CNTs,*** the model,the stress distributions along the CNT-CNT interface as well as in every individual CNT are well captured,and the failure propagation along the interface and its effects on the mechanical properties of the CNT bundles are *** work may provide useful guidelines for the design of novel CNT fibers in practice.

关键词： Carbon nanotube fiber Collagen-mimic design Staggered pattern Interface modification

High-temperature fatigue crack propagation study of superalloy GH4169 by single-lens 3D digital image correlation

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Science China(Technological Sciences) 2020年第4期63卷 693-704页

作者： YIN yuanjie HE Wei XIE HuiMin WU LiFu Key Laboratory of Applied Mechanics School of Aerospace EngineeringTsinghua UniversityBeijing 100084China

The characterization of fatigue crack propagation behavior is crucial for performance and reliability evaluation of aerospace *** this study,high-temperature(maximum:650℃)fatigue crack propagation experiments of Ni-based superalloy GH4169 were *** bi-prism-based single-lens 3D digital image correlation(BSL 3D DIC)technique was used to insitu measure the displacement and strain fields near fatigue crack *** on the deformation information,the modeΙstress intensity factor range△K and the crack opening displacement(COD)were determined for characterizing the crack closure *** the major fatigue crack growth model,the parameters of modified Paris’law were obtained based on the effective stress intensity factor range△Keff and the fatigue crack propagation rate(FCPR).Additionally,two kinds of J integrals,JP(path integral method)and JK(stress intensity factor K method),were used to evaluate the small-scale yielding approximation.

关键词： high-temperature fatigue Paris'law crack closure BSL 3D DIC

Impedance control of multi-arm space robot for the capture of non-cooperative targets

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Journal of Systems Engineering and Electronics 2020年第5期31卷 1051-1061页

作者： GE Dongming SUN Guanghui ZOU yuanjie SHI Jixin Beijing Institute of Spacecraft System Engineering China Academy of Space TechnologyBeijing 100094China Research Institute of Intelligent Control and Systems Harbin Institute of TechnologyHarbin 150001China

Robotic systems are expected to play an increasingly important role in future space activities. The robotic on-orbital service, whose key is the capturing technology, becomes a research hot spot in recent years. This paper studies the dynamics modeling and impedance control of a multi-arm free-flying space robotic system capturing a non-cooperative target. Firstly, a control-oriented dynamics model is essential in control algorithm design and code realization. Unlike a numerical algorithm, an analytical approach is suggested. Using a general and a quasi-coordinate Lagrangian formulation, the kinematics and dynamics equations are ***, an impedance control algorithm is developed which allows coordinated control of the multiple manipulators to capture a *** enforcing a reference impedance, end-effectors behave like a mass-damper-spring system fixed in inertial space in reaction to any contact force between the capture hands and the target. Meanwhile, the position and the attitude of the base are maintained stably by using gas jet thrusters to work against the manipulators' reaction. Finally, a simulation by using a space robot with two manipulators and a free-floating non-cooperative target is illustrated to verify the effectiveness of the proposed method.

关键词： multi-arm space robot impedance control non-cooperative target capture

Performance assessment of innovative seismic resilient steel knee braced frame

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Frontiers of Structural and Civil Engineering 2016年第3期10卷 291-302页

作者： Tony T. Y. YANG yuanjie LI International Joint Research Laboratory of Eearthquake Engineering 1239 Siping Road Shanghai 200002 China Department of Civil Engineering University of British Columbia Vancouver BC V6T1Z4 Canada

Buckling restrained knee braced truss moment frame （BRKBTMF） is a novel and innovative steel structural system that utilizes the advantages of long-span trusses and dedicated structural fuses for seismic applications. Steel trusses are very economical and effective in spanning large distance. However, conventional steel trusses are typically not suitable for seismic application, due to its lack of ductility and poor energy dissipation capacity. BRKBTMF utilizes buckling restrained braces （BRBs） as the designated structural fuses to dissipate the sudden surge of earthquake energy. This allows the BRKBTMF to economically and efficiently create large span structural systems for seismic applications. In this paper, a prototype BRKBTMF office building located in Berkeley, California, USA, was designed using performance-based plastic design procedure. The seismic performance of the prototype building was assessed using the state-of-the-art finite element software, OpenSees. Detailed BRB hysteresis and advanced element removal technique was implemented. The modeling approach allows the simulation for the force-deformation response of the BRB and the force redistribution within the system after the BRBs fracture. The developed finite element model was analyzed using incremental dynamic analysis approach to quantify the seismic performance of BRKBTMF. The results show BRKBTMF has excellent seismic performance with well controlled structural responses and resistance against collapse. In addition, life cycle repair cost of BRKBTMF was assessed using the next-generation performance-based earthquake engineering framework. The results confirm that BRKBTMF can effectively control the structural and non-structural component damages and minimize the repair costs of the structure under different ranges of earthquake shaking intensities. This studies conclude that BRKBTMF is a viable and effective seismic force resisting system.

关键词： buckling restrained brace innovative structural system collapse simulation seismic assessment

High Speed On/Off Valve Control Hydraulic Propeller

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Chinese Journal of Mechanical Engineering 2012年第3期25卷 463-473页

作者： ZHU Kangwu GU Linyi CHEN yuanjie LI Wei The State Key Lab of Fluid Power Transmission and Control Zhejiang UniversityHangzhou 310027China

The work-class remotely-operated-underwater-vehicles（ROVs） are mainly driven by hydraulic propulsion system,and the effeciency of hydraulic propulsion system is an important performance index of ***,the efficiency of traditional hydraulic propulsion system controlled by throttle valves is too ***,in this paper,for small and medium ROVs,a novel propulsion system with higher efficiency based on high speed on/off valve control hydraulic propeller is *** solve the conflict between large flow rate and high frequency response performance,a two-stage high speed on/off valve-motor unit with large flow rate and high response speed simultaneously is *** theoretical analysis,an effective fluctuation control method and a novel pulse-width-pulse-frequency-modulation（PWPFM） are introduced to solve the conflict among inherently fluctuation,valve dynamic performance and system efficiency.A simulation model is established to evaluate the system *** prove the advantage of system in energy saving,and test the dynamic control performance of high speed on/off valve control propeller,a test setup is developed and a series of comparative experiments is *** smimulation and experiment results show that the two-stage high speed on/off valve has an excellent dynamic response performance,and can be used to realize high accuracy speed *** experiment results prove that the new propulsion system has much more advantages than the traditional throttle speed regulation system in energy *** lowest efficiency is more than 40%.The application results on a ROV indicate that the high speed on/off valve control propeller system has good dynamic and steady-state control *** transient time is only about 1 s-1.5 s,and steady-state error is less than 5%.Meanwhile,the speed fluctuation is small,and the smooth propeller speed control effect is *** the premise of good propeller speed control performance,the proposed

关键词： high speed on/off valve fluctuation control pulse-width-pulse-frequency-modulation(PWPFM) hydraulic propulsion system remotely-operated-underwater-vehicle(ROV) energy saving system

Mechanical Response of Triply Periodic Minimal Surface Structures Manufactured by Selective Laser Melting with Composite Materials

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Acta Metallurgica Sinica(English Letters) 2022年第3期35卷 397-410页

作者： Shuaishuai Wei Bo Song yuanjie Zhang Lei Zhang Yusheng Shi State Key Laboratory of Materials Processing and Die&Mould Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China

It is of significance but remains a pivotal challenge to simultaneously enhance the strength and lightweight levels of porous *** provide an innovative strategy to improve the strength of porous structures with unchanged lightweight levels by applied composite *** laser melting(SLM)is convenient for integral forming of materials and ***,in this study,the research about the mechanical response of triply periodic minimal surfaces(TPMS)porous structures with 316 L and composites fabricated by SLM was *** compression test and finite element method(FEM)were used to characterize mechanical *** composite structures exhibit enhanced elastic modulus,yield strength,unvaried lightweight level and refined grain microstructure,which are difficult to realize for porous structures made by pure 316 L *** elastic modulus,yield strength,plateau stress and energy absorption of composites were 3187.50,67.73,15.24 and 17.09 MJ/m^(3),respectively.

关键词： Triply periodic minimal surfaces Mechanical property Fe-based amorphous alloy High specific strength