检索结果-南通市图书馆

Resonant frequencies of a piezoelectric drum transducer

在线全文

学校读者我要写书评

暂无评论

Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第9期10卷 1313-1319页

作者： Jiang-bo YUAN Tao XIE xiao-biao shan Wei-shan CHEN State Key Laboratory of Advanced Robot and System Harbin Institute of Technology Harbin 150001 China

This paper presents a piezoelectric-metal structure called a drum transducer. An equation for calculating the resonance frequency of the drum transducer is obtained based on thin plate elastic theory of piezoelectric and metal material combined with the Rayleigh-Ritz method. The finite element method (FEM) was used to predict the excitation frequency of the drum transducer. To verify the theoretical analysis, the input impedance characteristic of the drum transducer was measured using an experimental method. The results obtained from theoretical analysis were in very good agreement with those from the FEM and experimental results. The effect of geometrical changes to the thick-walled steel ring of the drum transducer at the first resonance frequency is also described. The calculated results were found to be in good agreement with the FEM results. The results indicate that the first resonance frequency of the drum decreases with the increasing inner diameter of the thick-walled steel ring.

关键词： Piezoelectric Drum transducer Resonance frequency

A simple approach for determining the preload of a wire race ball bearing

在线全文

学校读者我要写书评

暂无评论

Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2010年第7期11卷 511-519页

作者： xiao-biao shan Li-li WANG Tao XIE Wei-shan CHEN 1School of Mechatronics Engineering Harbin Institute of Technology Harbin 150001 China College of Science Northeast Forestry University Harbin 150040 China

Wire race ball bearings have been widely used in high-tech weapons. The preload of a wire race ball bearing is crucial in engineering applications. In this study, a more effective approach is proposed for exact determination of the wire race ball bearing preload. A new mathematical model of the preload and the starting torque of the wire race ball bearing was built using the theorem of the 3D rolling friction resistance and the non-conforming contact theory. Employing a wire race ball bearing with a 1000 mm diameter used in a specific type of aircraft simulating rotary table, the numerical analysis in MATLAB～ showed that the preload magnitude can be controlled in the range of 130–140 μm. As verification, the experimental results were in agreement with the theoretical results, and confirm the feasibility of this method. This new approach is more exact in the preload range of 10–158 μm than that computed by the numerical method reported in our previous work (shan et al., 2007b). This implies that the present method contributes to more effectively preventing rolling noise, overturning moments and wear of the wire race ball bearing. The current research provides critical technical support for the engineering application of wire race ball bearings with large diameters.

关键词： Wire race ball bearing Rolling friction Starting torque Contact interface

Science Letters:Energy harvesting with a slotted-cymbal transducer

在线全文

学校读者我要写书评

暂无评论

Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第8期10卷 1187-1190页

作者： Jiang-bo YUAN xiao-biao shan Tao XIE Wei-shan CHEN Department of Mechatronics Engineering Harbin Institute of Technology Harbin 150001 China

A cymbal transducer is made up of a piezoceramic disk sandwiched between two dome-shaped metal *** circumferential stresses caused by flexural motion of the metal endcaps can induce the loss of mechanical input *** element analysis shows that the radial slots fabricated in metal endcaps can release the circumferential stresses,and reduce the loss of mechanical input energy that could be converted into electrical *** this letter,the performance of a slotted-cymbal transducer in energy harvesting was *** results show that the output voltage and power of the cymbal are improved.A maximum output power of around 16 mW could be harvested from a cymbal with 18 cone radial slots across a 500 kΩ resistive load,which is approximately 0.6 times more than that of the original cymbal transducer.

关键词： Piezoelectric Cymbal transducer Energy harvesting

A new energy harvester using a piezoelectric and suspension electromagnetic mechanism

在线全文

学校读者我要写书评

暂无评论

Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2013年第12期14卷 890-897页

作者： xiao-biao shan Shi-wei GUAN Zhang-shi LIU Zhen-long XU Tao XIE School of Mechatronics Engineering Harbin Institute of Technology Shenyang Institute of Automation Chinese Academy of Science

This study presents a new design of a piezoelectric-electromagnetic energy harvester to enlarge the frequency bandwidth and obtain a larger energy *** harvester consists of a primary piezoelectric energy harvesting device,in which a suspension electromagnetic component is added.A coupling mathematical model of the two independent energy harvesting techniques was *** results show that the piezoelectric-electromagnetic energy harvester has three times the bandwidth and higher power output in comparison with the corresponding stand-alone,single harvesting mode *** finite element models of the piezoelectric and electromagnetic systems were developed,respectively.A finite element analysis was *** were carried out to verify the validity of the numerical simulation and the finite element *** shows that the power output and the peak frequency obtained from the numerical analysis and the finite element simulation are in good agreement with the experimental *** study provides a promising method to broaden the frequency bandwidth and increase the energy harvesting power output for energy harvesters.

关键词： Hybrid energy harvesting Piezoelectric Electromagnetic Environmental vibration

一种两自由度的压电-电磁复合能量收集器(英文)

在线全文

学校读者我要写书评

暂无评论

Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2014年第9期15卷 711-722页

作者： Hong-yan WANG Li-hua TANG Yuan GUO xiao-biao shan Tao XIE College of Computer and Control Engineering Qiqihar University State Key Laboratory of Robotics and System Harbin Institute of Technology Department of Mechanical Engineering University of AucklandAuckland 1010 New Zealand

研究目的:对一种两自由度的压电-电磁复合能量收集器进行发电性能研究。创新要点:建立了一种两自由度压电-电磁复合能量收集器发电性能的数学模型,该数学模型可以评估两自由度压电-电磁复合能量收集器中压电元件、电磁元件以及系统总输... 详细信息

研究目的:对一种两自由度的压电-电磁复合能量收集器进行发电性能研究。创新要点:建立了一种两自由度压电-电磁复合能量收集器发电性能的数学模型,该数学模型可以评估两自由度压电-电磁复合能量收集器中压电元件、电磁元件以及系统总输出功率。研究方法:对一种两自由度的压电-电磁复合能量收集器进行数学建模,并实验验证数学模型的正确性。基于实验测试得到的系统参数值,理论研究压电元件和电磁元件的机电耦合系数对不同能量收集器发电性能的影响关系,并对几种能量收集器的发电能力进行对比分析。重要结论:对于非强耦合(弱或中间耦合)的两自由度机电转换器,复合能量收集器(压电+电磁)具有比单一能量收集器(压电或电磁)更高的发电能力。

关键词：振动复合能量收集两自由度模型压电电磁

Treadmill exercise in combination with acousto-optic and olfactory stimulation improves cognitive function in APP/PS1 mice through the brain-derived neurotrophic factor-and Cygb-associated signaling pathways

在线全文

学校读者我要写书评

暂无评论

Neural Regeneration Research 2025年第9期20卷 2706-2726页

作者： biao xiao Chaoyang Chu Zhicheng Lin Tianyuan Fang Yuyu Zhou Chuxia Zhang Jianghui shan Shiyu Chen Liping Li Department of Physiology and Pharmacology Health Science CenterNingbo UniversityNingboZhejiang ProvinceChina Ningbo Key Laboratory of Behavioral Neuroscience Health Science CenterNingbo UniversityNingboZhejiang ProvinceChina Key Laboratory of Addiction Research of Zhejiang Province NingboZhejiang ProvinceChina

A reduction in adult neurogenesis is associated with behavioral abnormalities in patients with Alzheimer's ***,enhancing adult neurogenesis represents a promising therapeutic approach for mitigating disease symptoms and ***,nonpharmacological interventions aimed at inducing adult neurogenesis are currently *** individual non-pharmacological interventions,such as aerobic exercise,acousto-optic stimulation,and olfactory stimulation,have shown limited capacity to improve neurogenesis and cognitive function in patients with Alzheimer's disease,the therapeutic effect of a strategy that combines these interventions has not been fully *** this study,we observed an age-dependent decrease in adult neurogenesis and a concurrent increase in amyloid-beta accumulation in the hippocampus of amyloid precursor protein/presenilin 1 mice aged 2-8 *** deposition became evident at 4 months,while neurogenesis declined by 6 months,further deteriorating as the disease ***,following a 4-week multifactor stimulation protocol,which encompassed treadmill running(46 min/d,10 m/min,6 days per week),40 Hz acousto-optic stimulation(1 hour/day,6 days/week),and olfactory stimulation(1 hour/day,6 days/week),we found a significant increase in the number of newborn cells(5'-bromo-2'-deoxyuridine-positive cells),immature neurons(doublecortin-positive cells),newborn immature neurons(5'-bromo-2'-deoxyuridine-positive/doublecortin-positive cells),and newborn astrocytes(5'-bromo-2'-deoxyuridine-positive/glial fibrillary acidic protein-positive cells).Additionally,the amyloid-beta load in the hippocampus *** findings suggest that multifactor stimulation can enhance adult hippocampal neurogenesis and mitigate amyloid-beta neuropathology in amyloid precursor protein/presenilin 1 ***,cognitive abilities were improved,and depressive symptoms were alleviated in amyloid precursor protein/presenilin 1 mice

关键词： acousto-optic stimulation adult neurogenesis Alzheimer's disease amyloid precursor protein/presenilin 1 mice amyloid-beta deposition brain cell apoptosis cognitive impairment depression-like behavior involuntary treadmill exercise olfactory stimulation serum metabolites

A PIEZOELECTRIC ENERGY HARVESTER WITH VORTEX INDUCED VIBRATION

在线全文

学校读者我要写书评

暂无评论

A PIEZOELECTRIC ENERGY HARVESTER WITH VORTEX INDUCED VIBRATI...

Graphene Aerogel Composites with Self‑Organized Nanowires‑Packed Honeycomb Structure for Highly Efficient Electromagnetic Wave Absorption

2015全国压电和声波理论及器件技术研讨会

作者： Ru-jun SONG xiao-biao shan Jin-zhe LI Tao XIE Qi-gang SUN School of Mechatronics Engineering Harbin Institute of Technology College of Mechanical and Electrical Engineering Northeast Forestry University Economic and Technology Research Institute of shandong Electric Power Company

This paper presents a piezoelectric energy harvester（PEH）which can convert fluid kinetic energy into electricity with vortex induced vibration（VIV）.The PEH is composed by a piezoelectric cantilever beam and a cylinder *** response and energy harvesting of the PEH are studied *** is found that maximum output power can be obtained with optimal resistance and the more power output,the stronger elimination of vibration *** frequency makes greater contribution on power output at smaller cylinder diameter and decreases with increasing of cylinder *** amplitude plays main role on output power and increases first until reaching peak point with increasing of cylinder *** output power can be obtained with reasonable cylinder diameter.

关键词： Vortex-induced vibration Energy harvesting Piezoelectric

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

Nano-Micro Letters 2025年第2期17卷 533-547页

作者： xiao You Huiying Ouyang Ruixiang Deng Qiuqi Zhang Zhenzhong Xing xiaowu Chen Qingliang shan Jinshan Yang Shaoming Dong State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 200050People’s Republic of China Key Laboratory of Inorganic Coating Materials CAS Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 200050People’s Republic of China Structural Ceramics and Composites Engineering Research Center Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 200050People’s Republic of China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049People’s Republic of China School of Physical Science and Technology ShanghaiTech UniversityShanghai 201210People’s Republic of China School of Materials Science and Engineering Zhejiang Sci-Tech UniversityHangzhou 310018People’s Republic of China University of Chinese Academy of Sciences Beijing 100039People’s Republic of China

With vigorous developments in nanotechnology,the elaborate regulation of microstructure shows attractive potential in the design of electromagnetic wave ***,a hierarchical porous structure and composite heterogeneous interface are constructed successfully to optimize the electromagnetic loss *** macro–micro-synergistic graphene aerogel formed by the ice template‑assisted 3D printing strategy is cut by silicon carbide nanowires(SiC_(nws))grown in situ,while boron nitride(BN)interfacial structure is introduced on graphene *** unique composite structure forces multiple scattering of incident EMWs,ensuring the combined effects of interfacial polarization,conduction networks,and magnetic-dielectric ***,the as-prepared composites present a minimum reflection loss value of−37.8 dB and a wide effective absorption bandwidth(EAB)of 9.2 GHz(from 8.8 to 18.0 GHz)at 2.5 ***,relying on the intrinsic high-temperature resistance of SiC_(nws) and BN,the EAB also remains above 5.0 GHz after annealing in air environment at 600℃ for 10 h.

关键词： Hierarchical porous structure Interface High-temperature resistance Graphene aerogel composites Electromagnetic wave absorption

Novel approach for determining the optimal axial preload of a simulating rotary table spindle system

在线全文

学校读者我要写书评

暂无评论

Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第5期8卷 812-817页

作者： shan xiao-biao XIE Tao CHEN Wei-shan School of Mechatronics Engineering Harbin Institute of Technology Harbin 15001 China

This paper presents a new theoretical model to determine the optimal axial preload of a spindle system, for challenging the traditional method which relies heavily on experience of engineers. The axial preloading stiffness was treated as the sum of the spindle modal stiffness and the framework elastic stiffness, based on a novel concept that magnitude of preloads can be controlled by measuring the resonant frequency of a spindle system. By employing an example of a certain type of aircraft simulating rotary table, the modal stiffness was measured on the Agilent 35670A Dynamic Signal Analyzer by experimental modal analysis. The equivalent elastic stiffness was simulated by both finite element analysis in ANSYS? and a curve fitting in MATLAB?. Results showed that the static preloading stiffness of the spindle was 7.2125×107 N/m, and that the optimal preloading force was 120.0848 N. Practical application proved the feasibility of our method.

关键词： Three-axis simulating rotary table Axial position preload Stiffness Experimental modal analysis Finite elementanalysis