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Dynamic Scaling of Surface Growth in the Influence of Small Clusters Mobility

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Chinese Physics Letters 2000年第4期17卷 285-287页

作者： ZHUANG guo-ce WANG Wei National Laboratory of Solid State Microstructure and Department of Physics Nanjing UniversityNanjing 210093 Department of Physics Yancheng Teacher's CollegeJiangsu 224002

The deposition,diffusion and coalescence processes appeared in the surface growth of compact or liquid-like clusters system are *** introducing a critical cluster size ic,such that clusters of size s≤ic are mobile while clusters of the size s>ic are immobile,the effects of mobility of small clusters on cluster size distribution are *** ic increases,the exponentγwhich relates the maximum cluster density to the normalized deposition rate is *** simudation results indicate that the scaled cluster-size distributions are independent of the deposition rate,but closely associated with the small clusters *** ic increases,it is found that the distributions become narrow.

关键词： cluster narrow normalized

Structural design inspired by beetle elytra and its mechanical properties

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Chinese Science Bulletin 2012年第8期57卷 941-947页

作者： guo ce SONG WenWei DAI ZhenDong Institute of Bio-inspired Structure and Surface Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China

On the basis of the microstructure of the cross-section of a beetle's elytra,three bio-inspired lightweight structures were designed and built from acrylonitrile butadiene styrene plastic with a three-dimensional *** mechanical properties of three lightweight structures were analyzed and compared employing the finite element method,and quasi-static compression experiments and a three-point bending test on the structure samples were carried out using an electronic universal testing machine to verify the effectiveness of the finite element *** results show that all three bio-structures were lightweight and had excellent mechanical *** particular,the bio-structure with spherical holes and hollow columns perpendicular to the top and bottom surfaces best imitated the microstructure of the cross-section of the Cybister elytra and had the greatest specific strength/stiffness in compression and ***,a preliminary optimization design was obtained for this bio-structure to further improve its specific strength and specific stiffness to 31.82 kN m/kg and 108.73 kN m 2 /kg respectively.

关键词：微观结构机械性能鞘翅设计灵感甲虫静态压缩实验电子万能试验机有限元方法

Morphology and mechanical properties of Cybister elytra

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Chinese Science Bulletin 2010年第8期55卷 771-776页

作者： YANG ZhiXian DAI ZhenDong guo ce Institute of Bio-inspired Structure and Surface Engineering Nanjing University of Aeronautics and Astronautics Nanjing 210016 China College of Mechanical and Electrical Engineering Nanjing University of Aeronautics and Astronautics Nanjing 210016 China

The mechanical properties and the topological structure of cross-sections found in Cybister elytra are *** images show the similar geometric structure in transverse and longitudinal *** consist of several layers:a dense,black epicuticle,an exocuticle that is braided by several parallel chitin fiber layers in a helix structure,and many bridge piers formed by the fiber bundles that connect the exocuticle to the endodermis,forming a composite,light-weight *** mechanical properties along the edge of elytra are measured using a *** hardness and modulus of fresh cybister elytra is 0.31 GPa and 6.13 GPa,*** ultimate stresses of fresh elytra,measured by using a tensile test machine,are 169.2 MPa and 194.5 MPa in the transverse and longitudinal directions,respectively,which is twice higher than that of the dried *** difference in the two directions indicates that this bio-material has been topologically optimized during *** results may provide a biological template to inspire lightweight structure design for aerospace engineering.

关键词：力学性能鞘翅形态扫描电镜照片生物材料拉伸试验机拓扑结构几何结构

Atomic Aggregation Processes in the Early Stages of Pt/Pt(111)Growth

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Chinese Physics Letters 2000年第8期17卷 589-591页

作者： ZHUANG guo-ce ZHU Xiao-Bin WANG Wei National Laboratory of Solid State Microstructure and Department of Physics Nanjing UniversityNanjing 210093 Department of Physics Yancheng Teacher's CollegeYanchengJiangsu 224002

The atomic aggregation processes in the early stages of Pt/Pt(111)growth are studied by using kinetic Monte Carlo *** results show that the average neighbor coordination number of the atoms in a cluster is a function of temperature,agreeing well with the experiment observations of scanning tunneling *** influence of diffusion barriers of various atomic processes on the morphology of islands is also *** morphologies of the islands(dendritic,fractal,or compact islands)are found.

关键词： fractal atomic tunneling

Mechanical properties of a novel, lightweight structure inspired by beetle's elytra

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Chinese Science Bulletin 2014年第26期59卷 3341-3347页

作者： ce guo Dong Li Zhenyu Lu Chunsheng Zhu Zhendong Da Institute of Bio-inspired Structure and Surface Engineering Nanjing University of Aeronautics and Astronautics

A new kind of bio-inspired, lightweight structure was designed and built from carbon fibre prepreg based on the cross-sectional microstructure of a beetle's elytra. The compression strength and failure process of the resulting structure was analysed using the finite element method; while at the same time, a quasi-static compression experiment was performed using an electronic universal testing machine to verify the effectiveness and accuracy of this finite element method. This bio-inspired structure was compared against a conventional honeycomb structure using FEM, revealing that for a given porosity and load parallel to the axis of the core tubes the respective compressive and specific compressive strengths of the bioinspired structure are much higher at 84.3 MPa and194.7 MPa/(g cm-3); thus demonstrating that this bioinspired structure has superior compressive capability.

关键词：结构体机械性能鞘翅甲虫电子万能试验机灵感静态压缩试验压缩强度

A stereotaxic method and apparatus for the Gekko gecko

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Chinese Science Bulletin 2008年第7期53卷 1107-1112页

作者： WANG WenBo DAI ZhenDong TAN Hua guo ce SUN JiuRong Institute of Bioinspired Structure and Surface Engineering Nanjing University of Aeronautics and Astronautics Nanjing 210016 China College of Life Sciences Peking University Beijing 100871 China

To study the modulation mechanism of the middle brain of the Gekko to the locomotion, we introduced a stereotaxic method first in literature and developed an apparatus suitable for Gekko gecko, the big-gest wall and ceiling climber in nature. We defined the bregma and nasal points as reference points, selected the bilateral infraorbital margin and top point of the maxillary tooth for locating and fixing, and set up the line passing through the bregma and paralleling to a line connecting the bilateral infraorbital margin as x axis. Then, we defined a horizontal plane in the stereotaxic instrument, passing through x axis and the certain point which is 4.8 mm exactly above the nasal point, as the XOY plane; the sagittal plane, i.e. the YOZ plane, is the plane which is perpendicular to x axis and passes through the bregma; the plane, i.e. the XOZ plane, which passes through x axis and is perpendicular to the horizontal plane is the coronal plane. We designed a set of head holder which includes three parts: bilateral infraorbital margin clamps, a gecko adaptor holding the rostral side of the upper jaw. The allocation and operation of the head holder is accurate and simple, and the device is low in cost and compatible with standard stereotaxic instrument.

关键词：立体器械爬山虎攀缘植物双向性

Biomechanism of adhesion in gecko setae

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Science China(Life Sciences) 2012年第2期55卷 181-187页

作者： guo ce SUN JiuRong GE YingBin WANG WenBo WANG DaPeng DAI-ZhenDong Institute of Bio-inspired Structure and Surface Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China School of Life Science Peking UniversityBeijing 100873China School of Basic Medical Sciences Nanjing Medical UniversityNanjing 210029China Institute of Intelligent Machines Chinese Academy of SciencesHefei 230031China

The study of the adhesion of millions of setae on the toes of geckos has been advanced in recent years with the emergence of new technology and measurement methods. The theory of the mechanism of adhesion by van der Waals forces is now accepted and broadly understood. However, this paper presents limitations of this theory and gives a new hypothesis of the biomechanism of gecko adhesion. The findings are obtained through measurements of the magnitude of the adhesion of setae under three different conditions, to show the close relationship between adhesion and status of the setae. They are reinforced by demonstrating two setal structures, follicle cells and hair, the former making the setae capable of producing bioelectrical charges, which play an important role in attachment and detachment processes. It is shown that the abundant muscular tissues at the base of the setae cells, which are controlled by peripheral nerves, are instrumental in producing the foot movement involved in attachment and detachment. Our study will further uncover the adhesion mechanism of geckos, and provide new ideas for designing and fabricating synthetic setae.

关键词： gecko setae adhesion biomechanism microstructure bionics

Bionic Design Inspired by Surface Texture of Cybister's Elytra

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Transactions of Nanjing University of Aeronautics and Astronautics 2018年第S1期35卷 51-58页

作者： Han Cheng guo ce Xu Tao Institute of Bio-inspired Structure and Surface Engineering College of AstronauticNanjing University of Aeronautics and Astronautics College of Mechanical and Electrical Engineering Nanjing University of Aeronautics and Astronautics

Super depth digital microscope was employed to observe the macro-/micro-structure of Coleoptera's *** non-smooth surface textures of elytra have shown superior performance of friction reduction and *** models of regular hexagonal convex texture and circular concave texture inspired by the beetle were established and verified by numerical calculations and *** tribological experiments were performed and the results show that the circle texture has the lowest coefficient,which is consistent with the numerical *** research may be further applied to new bionic surface texture designs and also work as a biological template for new bionic inventions.

关键词： bionics surface textures simulation tribological test

Divisional and hierarchical innervations of G. gecko's toes to motion and reception

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Chinese Science Bulletin 2009年第16期54卷 2880-2887页

作者： guo ce CAI Lei XIE HeRui WANG ZhouYi DAI ZhenDong SUN JiuRong Institute of Bio-inspired Structure and Surface Engineering Nanjing University of Aeronautics and Astronautics Nanjing 210016 China College of Life Sciences Peking University Beijing 100871 China

As a member of robot families, climbing robots have become one of the research hot-spots in the robotic field recently and Gekko gecko (G. gecko) has been broadly seen as an ideal model for climbing robot development. But for gecko-mimic robots, one of the key problems is how to design the robot's foot. In this paper, (1) high-speed camera recording and electrophysiological method are used to observe motion patterns of G. gecko's foot when it climbs on different oriented surfaces; (2) nerve innervations of gecko's toes to motion and reception are studied. It is found that the five toes of the G. gecko can be divided into two motion and reception divisions, and also its motion and reception are modulated and controlled hierarchically. The results provide important information and exclusive ideas for the foot design and control algorithm of gecko-mimic robots.

关键词：大壁虎脚趾爬壁机器人分区控制算法仿生机器人家庭成员运动模式