Wind-induced vibration energy harvesting has a great potential for utilizing wind energy to supply power for low-powered devices.To improve the working performance of energy harvesters effectively,a suitable structura...Wind-induced vibration energy harvesting has a great potential for utilizing wind energy to supply power for low-powered devices.To improve the working performance of energy harvesters effectively,a suitable structural design is crucial.This paper proposes a dual-beam piezo-magneto-elastic wake-induced vibration energy harvesting system to enhance the functional performance of aeroelastic energy harvesters in environments with variable wind speeds.The system contains two piezoelectric beams coupled by magnets(forming upstream and downstream energy harvesters),and each beam is attached with a foam cylinder.A corresponding dynamic model is provided,and output characteristics are obtained at different wind speeds.Results and experimental verification indicate that both upstream and downstream energy harvesters can realize efficient energy harvesting.When the wind speed exceeds a certain critical value,the amplitudes of the system’s displacement and voltage are high.The wind speed threshold value is approximately 1.25 m/s.When the wind speed and magnet spacing are 10.2 m/s and 20 mm,respectively,the output power of the system reaches 4.9×10^(−4)W.Moreover,the wind speed threshold value of the proposed system can be adjusted by an equivalent nonlinear restoring force.展开更多
将聚焦离子束和扫描电子显微镜相整合而形成的双束系统——聚焦离子束扫描电子显微镜(Focused Ion Beam-Scanning Electron Microscopy,FIB-SEM)已成为对生物样品的超微结构进行成像和定量分析的有力工具。该系统既能对硬质生物材料进...将聚焦离子束和扫描电子显微镜相整合而形成的双束系统——聚焦离子束扫描电子显微镜(Focused Ion Beam-Scanning Electron Microscopy,FIB-SEM)已成为对生物样品的超微结构进行成像和定量分析的有力工具。该系统既能对硬质生物材料进行铣削,又能在纳米尺度完成对其三维结构的重建。更为重要的是,它还能将组织或器官的宏观形态与组成细胞的内部结构直接关联。本文介绍了FIB-SEM的工作原理和设备组成,对FIB-SEM三维成像在肿瘤及肿瘤干细胞模型、生物打印系统的铣削、成像和超微结构分析,以及癌细胞对纳米颗粒的摄入等肿瘤生物学领域的典型应用进行了概述,并对利用FIB-SEM三维定量和超微结构分析的方法研究线粒体和其他亚细胞结构与癌症发生的关系提出了展望。目的是强化FIB-SEM在肿瘤生物学领域的应用,以揭示肿瘤细胞超微形态和结构变化对肿瘤演进所起的作用,为肿瘤治疗提供新靶标。展开更多
The alkali-atom density measurement method based on light absorption is highly suitable for a spin-exchange relaxationfree(SERF)atomic magnetometer because of its high-precision measurement and complete nonmagnetic in...The alkali-atom density measurement method based on light absorption is highly suitable for a spin-exchange relaxationfree(SERF)atomic magnetometer because of its high-precision measurement and complete nonmagnetic interference.In this study,the optical rotation angle detection system based on polarization balance detection is utilized to realize the alkali-atom density real-time measurement without affecting magnetic field measurement.We discovered that there exists an optimal frequency detuning of the probe light,which offers the highest sensitivity in alkali-atom density measurement and the lowest susceptibility to temperature fluctuations in terms of the scale factor.In contrast to conventional light absorption measurements based on pump light,this method demonstrated a threefold improvement in alkali-atom density measurement sensitivity while remaining immune to ambient magnetic fields and incident light intensity fluctuations.Furthermore,we utilized this method to achieve closed-loop temperature control with an accuracy of 0.04℃.展开更多
基金supported by the National Natural Science Foundation of China(Grant No.52161135106)the Science,Technology and Innovation Commission of Shenzhen Municipality(Grant No.JCYJ201908061536-15091)+4 种基金the International Science and Technology Cooperation Project of Guangdong Province(Grant No.2021A0505030012)the Innovation Capability Support Plan of Shaanxi Province(Grant No.2020KJXX-021)the Innovation Foundation for Doctor Dissertation of Northwestern Polytechnical University(Grant No.CX2022001)the 111 Project(Grant No.BP0719007)supported by the National Science Centre,Poland under the project SHENG-2(Grant No.2021/40/Q/ST8/00362)。
文摘Wind-induced vibration energy harvesting has a great potential for utilizing wind energy to supply power for low-powered devices.To improve the working performance of energy harvesters effectively,a suitable structural design is crucial.This paper proposes a dual-beam piezo-magneto-elastic wake-induced vibration energy harvesting system to enhance the functional performance of aeroelastic energy harvesters in environments with variable wind speeds.The system contains two piezoelectric beams coupled by magnets(forming upstream and downstream energy harvesters),and each beam is attached with a foam cylinder.A corresponding dynamic model is provided,and output characteristics are obtained at different wind speeds.Results and experimental verification indicate that both upstream and downstream energy harvesters can realize efficient energy harvesting.When the wind speed exceeds a certain critical value,the amplitudes of the system’s displacement and voltage are high.The wind speed threshold value is approximately 1.25 m/s.When the wind speed and magnet spacing are 10.2 m/s and 20 mm,respectively,the output power of the system reaches 4.9×10^(−4)W.Moreover,the wind speed threshold value of the proposed system can be adjusted by an equivalent nonlinear restoring force.
文摘将聚焦离子束和扫描电子显微镜相整合而形成的双束系统——聚焦离子束扫描电子显微镜(Focused Ion Beam-Scanning Electron Microscopy,FIB-SEM)已成为对生物样品的超微结构进行成像和定量分析的有力工具。该系统既能对硬质生物材料进行铣削,又能在纳米尺度完成对其三维结构的重建。更为重要的是,它还能将组织或器官的宏观形态与组成细胞的内部结构直接关联。本文介绍了FIB-SEM的工作原理和设备组成,对FIB-SEM三维成像在肿瘤及肿瘤干细胞模型、生物打印系统的铣削、成像和超微结构分析,以及癌细胞对纳米颗粒的摄入等肿瘤生物学领域的典型应用进行了概述,并对利用FIB-SEM三维定量和超微结构分析的方法研究线粒体和其他亚细胞结构与癌症发生的关系提出了展望。目的是强化FIB-SEM在肿瘤生物学领域的应用,以揭示肿瘤细胞超微形态和结构变化对肿瘤演进所起的作用,为肿瘤治疗提供新靶标。
文摘The alkali-atom density measurement method based on light absorption is highly suitable for a spin-exchange relaxationfree(SERF)atomic magnetometer because of its high-precision measurement and complete nonmagnetic interference.In this study,the optical rotation angle detection system based on polarization balance detection is utilized to realize the alkali-atom density real-time measurement without affecting magnetic field measurement.We discovered that there exists an optimal frequency detuning of the probe light,which offers the highest sensitivity in alkali-atom density measurement and the lowest susceptibility to temperature fluctuations in terms of the scale factor.In contrast to conventional light absorption measurements based on pump light,this method demonstrated a threefold improvement in alkali-atom density measurement sensitivity while remaining immune to ambient magnetic fields and incident light intensity fluctuations.Furthermore,we utilized this method to achieve closed-loop temperature control with an accuracy of 0.04℃.
