Helicopter inspection of ultra high voltage （UHV） transmission lines has unmatched advantages compared to manual work due to the inspection angle and high-tech equipment on board, especially in detailed inspections ...Helicopter inspection of ultra high voltage （UHV） transmission lines has unmatched advantages compared to manual work due to the inspection angle and high-tech equipment on board, especially in detailed inspections of tower heads and defect-detections in virtue of infrared/ultraviolet techniques. This paper deals with some key technical problems in the inspections of i 000 kV UHVAC lines with a helicopter, such as the safe distance of live-line working, electromagnetic field intensity and flight control. Based on the study results, a set of UHV line inspection methods was worked out and applied to the inspection of live UHV lines.展开更多
Photoluminescence(PL) mechanism of carbon quantum dots(CQDs) remains controversial up to now even though a lot of approaches have been made. In order to do that, herein a PL color ladder from blue to near infrared of ...Photoluminescence(PL) mechanism of carbon quantum dots(CQDs) remains controversial up to now even though a lot of approaches have been made. In order to do that, herein a PL color ladder from blue to near infrared of CQDs with the absolute quantum yields higher than 70% were prepared via a one-pot hydrothermal synthesis route and separated by silica gel column.Time-correlated single photon counting measurements suggest that the electron transition takes in effect in the PL progress of the crystalline core-shell structured CQDs, and the PL properties could be coarsely adjusted by tuning the size of the crystalline carbon core owing to quantum confinement effects, and finely adjusted by changing the surface functional groups consisted shell owing to surface trap states,respectively. Both coarse and fine adjustments of PL, as optical and photoelectrical characterizations and density-functional theory(DFT) calculations have demonstrated, make it possible for top-level design and precise synthesis of new CQDs with specific optical properties.展开更多
文摘Helicopter inspection of ultra high voltage （UHV） transmission lines has unmatched advantages compared to manual work due to the inspection angle and high-tech equipment on board, especially in detailed inspections of tower heads and defect-detections in virtue of infrared/ultraviolet techniques. This paper deals with some key technical problems in the inspections of i 000 kV UHVAC lines with a helicopter, such as the safe distance of live-line working, electromagnetic field intensity and flight control. Based on the study results, a set of UHV line inspection methods was worked out and applied to the inspection of live UHV lines.
基金supported by the National Natural Science Foundation of China(21535006)
文摘Photoluminescence(PL) mechanism of carbon quantum dots(CQDs) remains controversial up to now even though a lot of approaches have been made. In order to do that, herein a PL color ladder from blue to near infrared of CQDs with the absolute quantum yields higher than 70% were prepared via a one-pot hydrothermal synthesis route and separated by silica gel column.Time-correlated single photon counting measurements suggest that the electron transition takes in effect in the PL progress of the crystalline core-shell structured CQDs, and the PL properties could be coarsely adjusted by tuning the size of the crystalline carbon core owing to quantum confinement effects, and finely adjusted by changing the surface functional groups consisted shell owing to surface trap states,respectively. Both coarse and fine adjustments of PL, as optical and photoelectrical characterizations and density-functional theory(DFT) calculations have demonstrated, make it possible for top-level design and precise synthesis of new CQDs with specific optical properties.
