The properties of piezoelectric PVDF films as separators are studied in NiO/Li electrodes Li-ion power cell.The results show that the PVDF piezoelectric film with excellent insulation is suitable for the environmental...The properties of piezoelectric PVDF films as separators are studied in NiO/Li electrodes Li-ion power cell.The results show that the PVDF piezoelectric film with excellent insulation is suitable for the environmental energy harvesting application.This is attributable to the compact structure of the piezoelectric PVDF film,and which make it has low leakage current and low charge-discharge current characteristics.展开更多
Aiming at the problems of loose bowl,nutritive bowl damage and planting leakage caused by lack of perception and detection of seedling clamping force in vegetable transplanting,a semi-micro-column structure sensor for...Aiming at the problems of loose bowl,nutritive bowl damage and planting leakage caused by lack of perception and detection of seedling clamping force in vegetable transplanting,a semi-micro-column structure sensor for measuring potted seedling clamping force was developed based on polyvinylidene fluoride(PVDF)piezoelectric film.The diameter of the semi-micro-column is 4 mm.The size of the force probe is 14 mm×30 mm,the encapsulation position of the force probe is 25 mm away from the tip of the seedling claw.The hardware circuit for sensor signal acquisition including pre-amplification module,power frequency notch module,low-pass filter module,processor module and power module was designed.The circuit completes charge-voltage conversion,clamping force signal amplification,power frequency signal elimination,vibration and noise elimination,and ensures the accurate acquisition of clamping force signal.In order to verify the sensor performance,sensor calibration tests and indoor experiments were carried out respectively.The calibration tests showed that the sensitivity of the clamping force sensor was 0.5264 V/N,the linearity was 4.74%,the accuracy was 6.51%,the hysteresis was 3.63%,and the range was 8 N under the impact of different waveforms and frequencies,which fully meet the accuracy requirements of the clamping force detection during transplanting.Indoor experiments showed that the clamping force sensor had good stability and adaptability under different seedling frequencies.The sensor can provide useful reference for the perception and detection of seedling clamping force and the feedback regulation of seedling clamping force.展开更多
基金financially supported by the National Natural Science Foundation of China(Grant Nos.11179038,10974073)the Specialized Research Fund for the Doctoral Program of Higher Education(Grant No.20120211130005)the Fundamental Research Funds for the Central Universities(Grant No.2022012zr0036)
文摘The properties of piezoelectric PVDF films as separators are studied in NiO/Li electrodes Li-ion power cell.The results show that the PVDF piezoelectric film with excellent insulation is suitable for the environmental energy harvesting application.This is attributable to the compact structure of the piezoelectric PVDF film,and which make it has low leakage current and low charge-discharge current characteristics.
基金sponsored by the National Key Research and Development Program of China Project(No.2016YFD0700100)the National Natural Science Foundation of China(No.51875175)+2 种基金the Key Research and Development Program of Guangdong Province(No.2019B020222004)the Innovation Scientists and Technicians Talent Projects of Henan Provincial Department of Education(No.19HASTIT021)the Innovation Scientists and Technicians Troop Construction Projects of Henan Province(No.184200510017).
文摘Aiming at the problems of loose bowl,nutritive bowl damage and planting leakage caused by lack of perception and detection of seedling clamping force in vegetable transplanting,a semi-micro-column structure sensor for measuring potted seedling clamping force was developed based on polyvinylidene fluoride(PVDF)piezoelectric film.The diameter of the semi-micro-column is 4 mm.The size of the force probe is 14 mm×30 mm,the encapsulation position of the force probe is 25 mm away from the tip of the seedling claw.The hardware circuit for sensor signal acquisition including pre-amplification module,power frequency notch module,low-pass filter module,processor module and power module was designed.The circuit completes charge-voltage conversion,clamping force signal amplification,power frequency signal elimination,vibration and noise elimination,and ensures the accurate acquisition of clamping force signal.In order to verify the sensor performance,sensor calibration tests and indoor experiments were carried out respectively.The calibration tests showed that the sensitivity of the clamping force sensor was 0.5264 V/N,the linearity was 4.74%,the accuracy was 6.51%,the hysteresis was 3.63%,and the range was 8 N under the impact of different waveforms and frequencies,which fully meet the accuracy requirements of the clamping force detection during transplanting.Indoor experiments showed that the clamping force sensor had good stability and adaptability under different seedling frequencies.The sensor can provide useful reference for the perception and detection of seedling clamping force and the feedback regulation of seedling clamping force.