Recently,hybrid energy harvester has been considered as an attractive potential approach to response the worldwide energy crisis due to the combination of advantages from different harvesting mechanism.In this paper,a...Recently,hybrid energy harvester has been considered as an attractive potential approach to response the worldwide energy crisis due to the combination of advantages from different harvesting mechanism.In this paper,a novel low-frequency wide-band hybrid energy harvester based on piezoelectric and triboelectric mechanism is presented and systematically studied including structural design,fabrication process,working principle simulation and measurement.With a vibrational excitation,the polyvinylidene fluoride(PVDF) cantilevers will vibrate and impact the polydimethylsiloxane(PDMS) film on the substrate,producing a piezoelectric output as well as a triboelectric output.The structural parameters of each cantilever are optimized using finite element simulation,and the well-designed PVDF cantilevers with controllable PDMS mass not only reduce the device working frequency but also enlarge the bandwidth.Under a sweep-frequency test,three voltage peaks induced by the piezoelectric part are observed at 15,32.5 and 47.5 Hz,with the value of 320,288 and 264 mV,respectively.With the combined triboelectric part,a 20 V peak-peak voltage is generated at 15 Hz.The electrical driving ability of this hybrid energy harvester also has been demonstrated by lighting up a commercial light emitting diode(LED).展开更多
针对微系统技术和产品发展的需求,通过模拟仿真设计保证了BGA在0.5~20.0 GHz范围内具有良好的宽带射频信号传输性能,并通过样件实测验证单个BGA的传输损耗和驻波比可以控制在0.5 d B和2以内。该结果可以为功能集成微系统提供一种高密度...针对微系统技术和产品发展的需求,通过模拟仿真设计保证了BGA在0.5~20.0 GHz范围内具有良好的宽带射频信号传输性能,并通过样件实测验证单个BGA的传输损耗和驻波比可以控制在0.5 d B和2以内。该结果可以为功能集成微系统提供一种高密度宽带数模混合信号垂直传输解决方案,同时将改变微系统功能单元的集成和互联形态。展开更多
To eliminate thermal stress and cracks in the process of laser cladding, a kind of bioceramic coating with gradient compositional design was prepared on the surface of Ti alloy by using wide-band laser cladding. And e...To eliminate thermal stress and cracks in the process of laser cladding, a kind of bioceramic coating with gradient compositional design was prepared on the surface of Ti alloy by using wide-band laser cladding. And effect of Y2O3 content on gradient bioceramic composite coating was studied. The experimental results indicate that adding rare earth can refine grain. Different rare earth contents affect formation of HA and β-TCP in bioceramic coating. When the content of rare earth ranges from 0.4% to 0.6%, the active extent of rare earth in synthesizing HA and β-TCP is the best, which indicates that “monosodium glutamate” effect of rare earth plays a dominant role. However, when rare earth content is up to 0.8%, the amount of synthesizing HA and β-TCP in coating conversely goes down, which demonstrates that rare earth gradually losts its catalysis in manufacturing HA and β-TCP.展开更多
基金supported by the National Natural Science Foundation of China (Grant Nos. 61176103,91023045)the National HiTech Research and Development Program of China ("863" Project) (Grant No.2013AA041102)+1 种基金the National Ph. D. Foundation Project (Grant No.20110001110103)the Global Research Outreach Program of Samsung Advanced Institute of Technology
文摘Recently,hybrid energy harvester has been considered as an attractive potential approach to response the worldwide energy crisis due to the combination of advantages from different harvesting mechanism.In this paper,a novel low-frequency wide-band hybrid energy harvester based on piezoelectric and triboelectric mechanism is presented and systematically studied including structural design,fabrication process,working principle simulation and measurement.With a vibrational excitation,the polyvinylidene fluoride(PVDF) cantilevers will vibrate and impact the polydimethylsiloxane(PDMS) film on the substrate,producing a piezoelectric output as well as a triboelectric output.The structural parameters of each cantilever are optimized using finite element simulation,and the well-designed PVDF cantilevers with controllable PDMS mass not only reduce the device working frequency but also enlarge the bandwidth.Under a sweep-frequency test,three voltage peaks induced by the piezoelectric part are observed at 15,32.5 and 47.5 Hz,with the value of 320,288 and 264 mV,respectively.With the combined triboelectric part,a 20 V peak-peak voltage is generated at 15 Hz.The electrical driving ability of this hybrid energy harvester also has been demonstrated by lighting up a commercial light emitting diode(LED).
文摘针对微系统技术和产品发展的需求,通过模拟仿真设计保证了BGA在0.5~20.0 GHz范围内具有良好的宽带射频信号传输性能,并通过样件实测验证单个BGA的传输损耗和驻波比可以控制在0.5 d B和2以内。该结果可以为功能集成微系统提供一种高密度宽带数模混合信号垂直传输解决方案,同时将改变微系统功能单元的集成和互联形态。
基金Project supported by Governor's Foundation of Guizhou Province (2004-07)
文摘To eliminate thermal stress and cracks in the process of laser cladding, a kind of bioceramic coating with gradient compositional design was prepared on the surface of Ti alloy by using wide-band laser cladding. And effect of Y2O3 content on gradient bioceramic composite coating was studied. The experimental results indicate that adding rare earth can refine grain. Different rare earth contents affect formation of HA and β-TCP in bioceramic coating. When the content of rare earth ranges from 0.4% to 0.6%, the active extent of rare earth in synthesizing HA and β-TCP is the best, which indicates that “monosodium glutamate” effect of rare earth plays a dominant role. However, when rare earth content is up to 0.8%, the amount of synthesizing HA and β-TCP in coating conversely goes down, which demonstrates that rare earth gradually losts its catalysis in manufacturing HA and β-TCP.
