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Bioinspired Scraper-File Type Frequency-Doubling Ultrasonic Exciter

Journal of Bionic Engineering 2024年第4期21卷 1801-1816页

作者： Wenshuai Wu Mingshuo Zhang Zeming Li Guang Yao Xinggang Jiang Deyuan Zhang School of Mechanical Engineering and Automation Beihang UniversityBeijing100191China Institute of Bionic and micro-nano Systems Beihang UniversityBeijing100191China Guangdong Provincial key laboratory of Minimally Invasive Surgical Instruments and manufacturing Technology Guangdong University of TechnologyGuangzhou510006China

In the natural world,leaf-cutting ants cause vibrations through their mutual scraping of file-scraper *** this study,we designed a Biomimetic Ultrasonic Exciter(BUE)that imitates leaf-cutting *** operating characteristics of the BUE were studied through experimental testing and finite element *** results showed that the BUE could generate stable ultrasonic vibrations,and that the excitation frequency only needed to be half the Output Frequency(OF).This frequency-doubling phenomenon was conducive to achieving BUE *** further explore the phenomenon of frequency-doubling vibration output,this study designed scrapers of five different sizes,conducted excitation and first-order natural frequency measurement tests,and the corresponding finite element *** was found that each scraper could operate in frequency-doubling mode,but the operating frequency and natural mode frequencies did not correspond with one *** further explicate experimental and simulation results,a two-degrees-of-freedom vibration model was *** was evident that the contact relationship between the dentate disc and scraper introduced strong nonlinear factors into the system,accounting for the frequency-doubling phenomenon and the difference between the BUE’s operating and mode *** BUE could be expected to facilitate the production of high-power micro-ultrasonic generators and has potential application value in the fields of mechanical processing,industrial production,and medical health.

关键词： Leaf-cutting ants Power ultrasound Nonlinear vibration Ultrasonic scalpel micro vibrator

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A Survey on Distributed Network Localization from a Graph Laplacian Perspective

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Journal of Systems Science & Complexity 2024年第1期37卷 273-293页

作者： HAN Zhimin LIN Zhiyun FU Minyue Artificial Intelligence Institute School of AutomationHangzhou Dianzi UniversityHangzhou 310018China shenzhen key laboratory of Control Theory and Intelligent Systems School of System Design and Intelligent ManufacturingSouthern University of Science and TechnologyShenzhen 518055China Peng Cheng laboratory Shenzhen 518000China

Network localization serves as a fundamental component for enabling various position based operations in multi-agent systems,facilitating tasks like target searching and formation control by providing accurate position information for all nodes in the *** localization focuses on the challenge of determining the positions of nodes within a network,relying on the known positions of anchor nodes and internode relative *** the past few decades,distributed network localization has garnered significant attention from *** paper aims to provide a review of main results and advancements in the field of distributed network localization,with a particular focus on the perspective of graph *** to its favorable characteristics,graph Laplacian unifies various network localization,even when dealing with diverse types of internode relative measurements,into a unified protocol framework,which can be constructed by a linear method and ensure the global convergence.

关键词： Distributed network localization graph Laplaian sensor network

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Surface reconstruction of heterostructures in alkaline medium towards enhanced electrocatalytic hydrogen evolution

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Rare Metals 2024年第6期43卷 2636-2647页

作者： Ming-Yang Yang Ji Yuan Xue-Lian Fu Jing-Jing Chen Jing Hu Zhou-Guang Lu Chen Liu Guangdong Research Center for Interfacial Engineering of Functional Materials Shenzhen Key Laboratory of Polymer Science and TechnologyShenzhen Key Laboratory of Energy Electrocatalytic MaterialsCollege of Materials Science and EngineeringShenzhen UniversityShenzhen 518060China shenzhen key laboratory of Interfacial Science and Engineering of Materials Department of Materials Science and EngineeringSouthern University of Science and TechnologyShenzhen 518055China

Constructing heterostructures has proved to be a successful strategy to fabricate electrocatalysts with high efficiency for water ***,the structure evolution in alkaline hydrogen evolution reaction lacks investigation and the specific active center remains ***,we take the well-designed Ni_(3)S_(2)@VO_(2) heterostructures as a model to investigate the electrocatalytic activity and the surface reconstruction process of heterostructure catalysts in alkaline *** Ni_(3)S_(2)@VO_(2) heterostructures,with Ni_(3)S_(2) nanorods as the core and VO_(2) nanoflakes as the shell,coupled with the high conductive Ni_(3)S_(2),the hydrophilic VO_(2) and modulated electronic structures at the interfaces,exhibited prominent activity and superior stability at various current ***,the ex-situ characterizations confirmed that the surface reconstruction from Ni_(3)S_(2)@VO_(2) into Ni_(3)S_(2)@amorphous-Ni(OH)_(2) in alkaline media could optimize the water dissociation barrier and exposed large active area,thereby contributing to improved electrocatalytic *** study not only introduces novel high-performance electrocatalysts for hydrogen evolution reaction(HER),but also provides a new avenue for re-examining hetero-structural catalysts in alkaline solutions.

关键词： Heterostructures Ni_(3)S_(2)@VO_(2) Surface reconstruction Water dissociation Alkaline hydrogen evolution

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Applications of genetic code expansion technology in eukaryotes

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Protein & Cell 2024年第5期15卷 331-363页

作者： Qiao-ru Guo Yu J.Cao State key laboratory of Chemical Oncogenomic Guangdong Provincial Key Laboratory of Chemical GenomicsPeking University Shenzhen Graduate SchoolShenzhen 518055China Institute of Chemical Biology Shenzhen Bay LaboratoryShenzhen 518132China

Unnatural amino acids(UAAs)have gained significant attention in protein engineering and drug development owing to their ability to introduce new chemical functionalities to *** eukaryotes,genetic code expansion(GCE)enables the incorporation of UAAs and facilitates posttranscriptional modification(PTM),which is not feasible in prokaryotic *** is also a powerful tool for cell or animal imaging,the monitoring of protein interactions in target cells,drug development,and switch ***,there is keen interest in utilizing GCE in eukaryotic *** review provides an overview of the application of GCE in eukaryotic systems and discusses current challenges that need to be addressed.

关键词： genetic code expansion unnatural amino acid eukaryotes basic research therapeutic applications

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Flat-top beam illumination for polarization-sensitive second-harmonic generation microscopy

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Chinese Optics Letters 2024年第6期22卷 164-169页

作者： Bing Wang Xiang Li Wenhui Yu Binglin Shen Rui Hu Junle Qu Liwei Liu State key laboratory of Radio Frequency Heterogeneous Integration Shenzhen UniversityShenzhen 518060China key laboratory of Optoelectronic Devices and Systems of Guangdong Province and Ministry of Education College of Physics and Optoelectronic EngineeringShenzhen UniversityShenzhen 518060China

Wide-field second-harmonic generation (SHG) was used to obtain the second-harmonic signal from the entire image area for rapid imaging, despite the fact that conventional Gaussian beam illumination has low energy utilization efficiency,which makes it easy to overexpose the intensity of the image center area. However, flat-top beam illumination has uniform spatial distribution, thereby improving the photon excitation efficiency in the entire image region and reducing laser damage and thermal effect. By combining flat-top beam illumination and wide-field SHG polarization measurement, we can calculate more myosin fibril symmetrical axis orientations through polarization analysis of 16 images at a fast imaging speed while expanding the field of view. More importantly, the application of a flat-top beam can further improve the capability of polarization measurement in SHG microscopy.

关键词： flat-top beam second-harmonic generation muscle structure

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Three‑Dimensional nano‑displacement Measurement by Four‑Beam Laser Interferometry

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nanomanufacturing and Metrology 2024年第2期7卷 42-49页

作者： Xu Zhang Zi Wang Mengnan Liu Zhengxun Song Zuobin Wang Litong Dong International Research Centre for nano Handling and manufacturing of China Changchun University of Science and TechnologyChangchun 130022China Centre for Opto/Bio‑nano Measurement and manufacturing Zhongshan Institute of Changchun University of Science and TechnologyZhongshan 528437China Ministry of Education key laboratory for Cross‑Scale micro and nano manufacturing Changchun University of Science and TechnologyChangchun 130022China JR3CN&IRAC University of BedfordshireLuton LU13JUUK

A 3D nano-displacement measurement method,where the difference in phase between the beams in a four-beam laser interference is changed,is *** results demonstrate that the variation of phase difference causes the deviation of the interference pattern in the laser interference *** on this theory,we design and build a four-beam laser interference *** corner cube prism in the optical path is shifted,and the phase of the beam is changed by applying different voltages to a piezoelectric *** phase difference is obtained by analyzing the lattice pattern with subpixel precision,and then the displacement is determined by correlation *** experimental measurement results are consistent with the theoretical analysis,thereby verifying the feasibility of this measurement method.

关键词： Four-beam laser interferometry Phase difference 3D displacement Correlation operation

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Iterative multi-photon adaptive compensation technique for deep tissue two-photon fluorescence lifetime imaging

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Chinese Optics Letters 2024年第4期22卷 89-94页

作者：王柯欣余文慧屈军乐廖常锐王义平何俊刘丽炜 State key laboratory of Radio Frequency Heterogeneous Integration(shenzhen University) Shenzhen 518060China key laboratory of Optoelectronic Devices and Systems of Guangdong Province&Ministry of Education College of Physics and Optoelectronic EngineeringShenzhen UniversityShenzhen 518060China

Fluorescence lifetime imaging can reveal the high-resolution structure of various biophysical and chemical parameters in a microenvironment ***,the depth of imaging is generally limited to hundreds of micrometers due to aberration and light scattering in biological *** paper introduces an iterative multi-photon adaptive compensation technique(IMPACT)into a two-photon fluorescence lifetime microscopy system to successfully overcome aberrations and multiple scattering problems in deep *** shows that 400 correction modes can be achieved within 5 min,which was mainly limited by the frame rate of a spatial light *** system was used for high-resolution imaging of mice brain tissue and live zebrafish,further verifying its superior performance in imaging quality and photon accumulation speed.

关键词： adaptive optics iterative optimization two-photon fluorescence lifetime imaging microscopy wavefront correction

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Towards Sustainable Grinding of Difficult-to-Cut Alloys-A Holistic Review and Trends

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Chinese Journal of Mechanical Engineering 2024年第2期37卷 1-28页

作者： Ning Qian Jiajia Chen Aqib Mashood Khan Biao Zhao Yurong Chen Wenfeng Ding Yucan Fu Jiuhua Xu Jiangsu key laboratory of Precision and micro-manufacturing Technology Nanjing University of Aeronautics and AstronauticsNanjing 210016China College of Mechanical and Electronic Engineering Nanjing Forestry UniversityNanjing 210037China JITRI Institute of Precision manufacturing Nanjing 211805China

Grinding,a critical precision machining process for difficult-to-cut alloys,has undergone continual technological advancements to improve machining ***,the sustainability of this process is gaining heightened attention due to significant challenges associated with the substantial specific grinding energy and the extensive heat generated when working with difficult-to-cut alloys,renowned for their exceptional physical and mechanical *** response to these challenges,the widespread application of massive coolant in manufacturing industries to dissipate grinding heat has led to complex post-cleaning and disposal ***,in turn,has resulted in issues such as large energy consumption,a considerable carbon footprint,and concerns related to worker health and safety,which have become the main factors that restrict the development of grinding *** paper provides a holistic review of sustainability in grinding difficult-to-cut alloys,encompassing current trends and future *** examination extends to developing grinding technologies explicitly tailored for these alloys,comprehensively evaluating their sustainability ***,the exploration delves into innovative sustainable technologies,such as heat pipe/oscillating heat pipe grinding wheels,minimum quantity lubrication,cryogenic cooling,and *** groundbreaking technologies aim to reduce dependence on hazardous coolants,minimizing energy and resource consumption and carbon emissions associated with coolant-related or subsequent disposal *** essence of these technologies lies in their potential to revolutionize traditional grinding practices,presenting environmentally friendly ***,future development trends and research directions are put forward to pursue the current limitation of sustainable grinding for difficult-to-cut *** paper can guide future research and development efforts toward more environmentally friendly

关键词： Grinding Sustainability Cooling Energy consumption Carbon footprint Difficult-to-cut alloys

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Dynamic Response of Foundations during Startup of High-Frequency Tunnel Equipment

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Computer Modeling in Engineering & Sciences 2024年第7期140卷 821-844页

作者： Dawei Ruan Mingwei Hu College of Civil and Transportation Engineering Shenzhen UniversityShenzhen518060China State key laboratory of Intelligent Geotechnics and Tunnelling Shenzhen UniversityShenzhen518060China key laboratory of Coastal Urban Resilient Infrastructures of Ministry of Education Shenzhen UniversityShenzhen518060China Underground Polis Academy Shenzhen UniversityShenzhen518060China shenzhen key laboratory of Green Efficient and Intelligent Construction of Underground Metro StationShenzhen UniversityShenzhen518060China

The specialized equipment utilized in long-line tunnel engineering is evolving towards large-scale,multifunctional,and complex *** vibration caused by the high-frequency units during regular operation is supported by the foundation of the units,and the magnitude of vibration and the operating frequency fluctuate in different engineering contexts,leading to variations in the dynamic response of the *** high-frequency units yield significantly diverse outcomes under different startup conditions and times,resulting in failure to meet operational requirements,influencing the normal function of the tunnel,and causing harm to the foundation structure,personnel,and property in severe *** article formulates a finite element numerical computation model for solid elements using three-dimensional elastic body theory and integrates field measurements to substantiate and ascertain the crucial parameter configurations of the finite element *** proposing a comprehensive startup timing function for high-frequency dynamic machines under different startup conditions,simulating the frequency andmagnitude variations during the startup process,and suggesting functions for changes in frequency and magnitude,a simulated startup schedule function for high-frequency machines is created through *** into account the selection of the transient dynamic analysis step length,the dynamic response results for the lower dynamic foundation during its fundamental frequency crossing process are *** validation checks if the structural magnitude surpasses the safety threshold during the critical phase of unit startup traversing the structural resonance *** design recommendations for high-frequency units’dynamic foundations are provided,taking into account the startup process of the machine and ensuring the safe operation of the tunnel.

关键词： Tunnel equipment high-frequency units startup conditions transient dynamics dynamic response foundation design

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Dynamically enhanced Autler–Townes splitting by orthogonal XUV fields

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Chinese Physics B 2024年第7期33卷 344-350页

作者：吴立龙姜维超彭良友 Institute of Quantum Precision Measurement College of Physics and Optoelectronic EngineeringShenzhen UniversityShenzhen 518060China State key laboratory for Mesoscopic Physics and Frontiers Science Center for nano-optoelectronics School of PhysicsPeking UniversityBeijing 100871China

Based on numerical solutions of the time-dependent Schr ¨odinger equation, we theoretically investigate the photoelectron spectrum of hydrogen atoms ionized by a pair of ultrashort, intense, and orthogonally polarized laser pulses with a relative time delay in a pump–probe configuration. The pump pulse resonantly excites electrons from the 1s and 2p levels,inducing Rabi oscillations. The resulting dynamically enhanced Autler–Townes(AT) splitting is observed in the photoelectron energy spectrum upon interaction with the second probe pulse. In contrast to the previous parallel-polarization scheme, the proposed orthogonal-polarization configuration enables the resolution of dynamically enhanced AT splitting over a considerably wider range of probe photon energies.

关键词： Autler–Townes splitting orthogonal XUV fields photoelectron spectra Rabi frequency

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