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Design and In Situ Additive Manufacturing of Multifunctional Structures

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Engineering 2023年第9期28卷 58-68页

作者： Yan zhang guangyu zhang Jing Qiao Longqiu Li State Key Laboratory of Robotics and System Harbin Institute of TechnologyHarbin 150001China School of Materials Science and Engineering Harbin Institute of TechnologyHarbin 150001China

Multifunctional structures(MFSs)integrate diverse functions to achieve superior ***,conventional design and manufacturing methods—which generally lack quality control and largely depend on complex equipment with multiple stations to achieve the integration of distinct materials and devices—are unable to satisfy the requirements of MFS applications in emerging industries such as aerospace *** by the concept of design for manufacturing,we adopt a layer regulation method with an established optimization model to design typical MFSs with load-bearing,electric,heat-conduction,and radiation-shielding functions.A high-temperature in situ additive manufacturing(AM)technology is developed to print various metallic wires or carbon fiber-reinforced high-meltingpoint polyetheretherketone(PEEK)*** is found that the MFS,despite its low mass,exceeds the stiffness of the PEEK substrate by 21.5%.The embedded electrics remain functional after the elastic deformation *** with those of the PEEK substrate,the equivalent thermal conductivity of the MFS beneath the central heat source area is enhanced by 568.0%,and the radiation shielding is improved by 27.9%.Moreover,a satellite prototype with diverse MFSs is rapidly constructed as an *** work provides a systematic approach for high-performance design and advanced manufacturing,which exhibits considerable prospects for both the function expansion and performance enhancement of industrial equipment.

关键词： Additive manufacturing Multifunctional structure Optimal design Satellite Polyetheretherketone

Research on the Effect Evaluation of Protected Space Driving New Technologies Industrialization from the Perspective of ST

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Journal of Systems Science & Complexity 2020年第2期33卷 475-509页

作者： LIU Yixin OU Chunyao zhang guangyu LIANG Xiao School of Management Guangdong University of TechnologyGuangzhou 510520China Guangdong Provincial Decision-making Consulting Research Base Research Centre for Innovation Theory and Innovation Management of Guangdong University of TechnologyGuangzhou 510520China

Based on the perspective of sustainability transitions(ST)theory,the paper dissects the opera-tional mechanisms of protected space driving emerging technology industrialization from an external system perspective,which is on the basis of defining essential characteristics and func-tional attributes of protected ***,it structures a three-dimensional evaluation model of protected space from the perspective of internal mechanism by introducing the policy mixes ***,taking the Chinese New Energy Vehicle(NEV)industry as the example and using the system dynamics modeling method,the paper designs different simulation schemes from three dimensions of horizontal evolution trend,three types of policy instrument change and policy mixes of protected space,to predict and analyze the operation effect of protected *** results show that the Chinese NEV industry is in the stage of market niche entry,and corresponding measures should be taken to increase the market scale,form effective demand and scale effect,and promote the diffusion of market niche;the effect of policy mixes is better than that of the single policy instrument;specific policy mixes should be adopted to develop simultaneously from both the supply and demand sides to improve the industrialization level of NEV.

关键词： Effect evaluation emerging technology industrialization policy mixes protected space sustainability transitions

A Bioinspired Soft Robot Combining the Growth Adaptability of Vine Plants with a Coordinated Control System

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Research 2021年第1期2021卷 1266-1273页

作者： Pengchun Li Yongchang zhang guangyu zhang Dekai Zhou Longqiu Li State Key Laboratory of Robotics and Systems Harbin Institute of TechnologyHarbinHeilongjiang 150001China

Tip-extending soft robots,taking flexible film or rubber as body material and fluid pressure as input power,exhibit excellent advantages in constrained and cluttered environments for detection and ***,existing soft continuum robots are of great challenges in achieving multiple,mutually independent,and on-demand active steering over a long distance without precise steering *** this paper,we introduce a vine-like soft robot made up of a pressurized thin-walled vessel integrated with the high controllability of a control system with multiple degrees of freedom in three ***,steering and kinematic models to relate the steering angle and robot length to the location of the robot tip are provided,and a dynamic finite element model for analyzing the motion of the spatial consecutive steering is *** demonstrate the abilities of disinfection of the robot moving in a long and tortuous pipeline and detection in a multi-obstacle constrained *** is established that the robot exhibits great advantages in active consecutive steering over a long distance,high controllability in completing more complex path planning,and significant ability of carrying operational tools for ventilation pipeline disinfection and multi-obstacle *** bionic soft robot shows great promise for use in environment sensing,target detecting,and equipment servicing.

关键词： robot Robot obstacle

Theoretical model of azimuthal combustion instability subject to non-trivial boundary conditions

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Chinese Journal of Aeronautics 2024年第9期37卷 113-130页

作者： Lei QIN Xiaoyu WANG guangyu zhang Xiaofeng SUN Research Institute of Aero-Engine Beihang UniversityBeijing 100191China School of Energy and Power Engineering Beihang UniversityBeijing 100191China

The problem of evaluating the sensitivity of non-trivial boundary conditions to the onset of azimuthal combustion instability is a longstanding challenge in the development process of modern gas *** difficulty lies in how to describe three-dimensional in-and outlet boundary conditions in an artificial computational *** date,the existing analytical models have still failed to quantitatively explain why the features of the azimuthal combustion instability of a combustor in laboratory environment are quite different from that in a real gas turbine,making the stability control devices developed in laboratory generally lose the effectiveness in practical *** overcome this limitation,we provide a novel theoretical framework to directly include the effect of non-trivial boundary conditions on the azimuthal combustion instability.A key step is to take the non-trivial boundary conditions as equivalent distributed sources so as to uniformly describe the physical characteristics of the inner surface in an annular enclosure along with different in-and outlet ***,a dispersion relation equation is established by the application of three-dimensional Green's function approach and generalized impedance *** show that the effects of the generalized modal reflection coefficients on azimuthal unstable modes are extremely prominent,and even prompt the transition from stable to unstable mode,thus reasonably explaining why the thermoacoustic instability phenomena in a real gas turbine are difficult to observe in an isolated combustion ***,this work provides an effective tool for analysis of the azimuthal combustion instability including various complicated boundary conditions.

关键词： Combustion instability Aeroacoustics Modeling Optimization techniques Control

Graphene： Nanostructure engineering and applications

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Frontiers of physics 2017年第1期12卷 1-22页

作者： Tingting zhang Shuang Wu Rong Yang guangyu zhang 1Institute of Physics Chinese Academy of Sciences Beijing 100190 China School of Physical Sciences University of Chinese Academy of Sciences Beijing 100190 China Beijing Key Laboratory for Nanomaterials and Nanodevices Beijing 100190 China Collaborative Innovation Center of Quantum Matter Beijing 100190 China

Graphene has attracted extensive research interest in recent years because of its fascinating physical properties and its potential for various applications. The band structure or electronic properties of graphene are very sensitive to its geometry, size, and edge structures, especially when the size of graphene is below the quantum confinement limit. Graphene nanoribbons （GNRs） can be used as a model system to investigate such structure-sensitive parameters. In this review, we examine the fabrication of GNRs via both top-down and bottom-up approaches. The edge-related electronic and transport properties of GNRs are also discussed.

关键词： graphene nanoribbons (GNRs) microfabrication top-down bottom-up electronic transport zigzag mobility edge state

Acoustic scattering mechanism and noise attenuation of circumferentially non-uniform liner with spectral-wave guide method

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Chinese Journal of Aeronautics 2023年第9期36卷 63-78页

作者： Wei DAI Xuli WANG Xiaoyu WANG guangyu zhang Xiaofeng SUN School of Energy and Power Engineering Beihang UniversityBeijing 100191China Research Institute of Aero-Engine Beihang UniversityBeijing 100191China

In this paper,a model is established with application of the spectral-wave guide method,which has higher accuracy and can serve as a rapid calculation tool for sound transmission *** on this calculation model,some numerical results of circumferentially non-uniform lined annular/circular ducts are carried out,and some physical mechanisms can be *** numerical results show that periodical impedance distributions along the circumferential direction will lead to discontinuous scattered modes with regular spacing;and mirror-symmetric structure liner will converge the energy of opposite *** on this mechanism,the potential of acoustic scattering can be further developed by suppressing lower or enhancing higher order modes with expressly designed segmented liner *** particular,the intrinsic mechanism of mode redistribution brought about by the non-uniform liner can be subtly utilized to attenuate broadband *** present work indeed shows that circumferentially non-uniform liner is conducive to the reduction of the practical broadband sound ***,the effects of nonuniform flow are considered in the model,then distinction of noise attenuation and scattered modes energy in different flows is shown.A possible mechanism is proposed that refraction effects in complex flows lead to the *** works show that the current model has profound potential and availability for the research and designs of circumferentially non-uniform liner.

关键词： Acoustic wave propagation Acoustic scattering Circumferentially nonuniform liner Noise attenuation Non-uniform flow Spectral-wave guide method

Monolayer MoS_(2) epitaxy

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Nano Research 2021年第6期14卷 1598-1608页

作者： Zheng Wei Qinqin Wang Lu Li Rong Yang guangyu zhang Beijing National Laboratory for Condensed Matter Physics and Institute of Physics Chinese Academy of SciencesBeijing100190China School of Physical Sciences University of Chinese Academy of SciencesBeijing100190China Songshan Lake Materials Laboratory Dongguan523808China

As an emerging two-dimensional(2D)semiconductor material,monolayer MoS2 has recently attracted considerable *** promising applications of this material have been proposed for electronics,optoelectronics,sensing,catalysis,energy storage,and so *** realize these practical applications,high-quality and large-area MoS2 with controllable properties is *** the many different synthesis techniques,epitaxy provides a promising route for producing MoS2 ***,we review the epitaxial growth of monolayer MoS2 on various substrates,with a particular focus on large-scale films with large domain sizes and high domain ***,we offer perspectives and challenges for future research and applications of this technology.

关键词： monolayer MoS_(2) epitaxy domain size domain alignment heterostructures

Low-Frequency Reciprocating Fretting Wear Testing System Design and Experiment Research

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Journal of Harbin Institute of Technology(New Series) 2015年第4期22卷 62-65页

作者： Zhongnan Wang Wuyi Wang guangyu zhang School of Mechatronics Engineering Harbin Institute of Technology

The fretting wear is resulted from different or same sample's surfaces by the small variationand leads to mechanism failures. The main factors consist of the variation of normal load and oscillation frequencies,among which surface topography of different materials are the main factors to the problems of the fretting ***,a novel low-frequency reciprocating fretting wear test system is designed upon the principle of Friction coefficient measurement. Four metal and non-metallic samples are measured under various normal load and oscillation frequencies to obtain the instantaneous friction coefficient in the repeat experiments. In fact,the experimental results show that Co F curves of different samples with the increase of the normal load are the similar exponential decay or parabolic shapes,which are consistent with the literatures to verify the rational design and reliable-operation of the system under the conditions of different frequencies.

关键词： fretting wear measuring-head reciprocating platform coefficient of friction oscillation frequency

Characterization of Arabidopsis MYB transcription factor gene AtMYB17 and its possible regulation by LEAFY and AGL15

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Journal of Genetics and Genomics 2009年第2期36卷 99-107页

作者： Yunfei zhang guangyu Cao Li-Jia Qu Hongya Gu National Laboratory of Protein Engineering and Plant Genetic Engineering College of Life Sciences Peking University Beijing 100871 China

MYB transcription factors compose one of the largest transcription factor families in Arabidopsis, which play important roles in vari- ous developmental processes as well as defense responses against environmental stresses. In this study, we report the characterization of AtMYB17 gene, a putative R2R3 type MYB gene family member in Arabidopsis. AtMYB17 was found exclusively localized in nuclear, with an activation domain at its C-terminus. AtMYBI7 was highly expressed in inflorescences and siliques, especially at early flower developmental stages. The level of AtMYB17 transcripts was also found to increase after imbibition during seed germination and gradually concentrate to the shoot apex. Bioinformatics analysis identified several binding sites of LEAFY （LFY） and AGL15 in the promoter re- gion of AtMYB17. Promoter-GUS fusion analysis showed that the LFY binding sites were important in fine-tuning regulation of the spatio-temporal expression ofAtMYB17 in transgenic plants. Moreover, AtMYB17 was up-regulated in 35S：：AGL15 plants. Taken together, our data suggest that LFY may be involved in the regulation of AtMYB17, possibly together with AGL 15, and thereafter in early inflores- cence development and seed germination.

关键词： AtMYB17 transcription factor Arabidopsis LEAFY AGL 15