The Extreme Ultraviolet Camera (EUVC) onboard the Chang'e-3 (CE-3) lander is used to observe the structure and dynamics of Earth's plasmasphere from the Moon. By detecting the resonance line emission of helium i...The Extreme Ultraviolet Camera (EUVC) onboard the Chang'e-3 (CE-3) lander is used to observe the structure and dynamics of Earth's plasmasphere from the Moon. By detecting the resonance line emission of helium ions (He+) at 30.4 nm, the EUVC images the entire plasmasphere with a time resolution of 10 min and a spatial resolution of about 0.1 Earth radius (RE) in a single frame. We first present details about the data processing from EUVC and the data acquisition in the commissioning phase, and then report some initial results, which reflect the basic features of the plas- masphere well. The photon count and emission intensity of EUVC are consistent with previous observations and models, which indicate that the EUVC works normally and can provide high quality data for future studies.展开更多
As one of the key units of space CCD camera,the temperature range and stability of CCD components affect the image's indexes.Reasonable thermal design and robust thermal control devices are needed.One kind of temp...As one of the key units of space CCD camera,the temperature range and stability of CCD components affect the image's indexes.Reasonable thermal design and robust thermal control devices are needed.One kind of temperature control loop heat pipe(TCLHP) is designed,which highly meets the thermal control requirements of CCD components.In order to study the dynamic behaviors of heat and mass transfer of TCLHP,particularly in the orbital flight case,a transient numerical model is developed by using the well-established empirical correlations for flow models within three dimensional thermal modeling.The temperature control principle and details of mathematical model are presented.The model is used to study operating state,flow and heat characteristics based upon the analyses of variations of temperature,pressure and quality under different operating modes and external heat flux variations.The results indicate that TCLHP can satisfy the thermal control requirements of CCD components well,and always ensure good temperature stability and uniformity.By comparison between flight data and simulated results,it is found that the model is to be accurate to within 1℃.The model can be better used for predicting and understanding the transient performance of TCLHP.展开更多
A method based on the XYZLMS interim connection space is proposed to accurately acquire the multi-spectral images by digital still cameras. The XYZLMS values are firstly predicted from RGB values by polynomial model w...A method based on the XYZLMS interim connection space is proposed to accurately acquire the multi-spectral images by digital still cameras. The XYZLMS values are firstly predicted from RGB values by polynomial model with local training samples and then spectral reflectance is constructed from XYZLMS values by pseudo-inverse method. An experiment is implemented for multi-spectral image acquisition based on a commercial digital still camera. The results indicate that multi-spectral images can be accurately acquired except the very dark colors.展开更多
Incipient plasmonic bubble formation is observed around gold nanopillars with different inter-nanopillar separations. The experimental measurements and theoretical analysis show that the nanobubble formation is due to...Incipient plasmonic bubble formation is observed around gold nanopillars with different inter-nanopillar separations. The experimental measurements and theoretical analysis show that the nanobubble formation is due to the enhanced plasmonic resonance rather than from the laser heating. Inter-nanopillar distribution may lead to threshold fluence variations. The lifetime of plasmonic bubbles can reach several minutes. Furthermore, both the radius and the growth rate of the plasmonic nanobubble increase as the inter-nanopillar distribution decreases.Smaller-spacing distributed arrays produced larger bubbles. The maximum growth rate of the bubbles can be reached at about 883.5 × 10^-6m∕s on 1 μm nanopillars, but it is only 56.9 × 10^-6m∕s on 4 μm nanopillars.展开更多
文摘The Extreme Ultraviolet Camera (EUVC) onboard the Chang'e-3 (CE-3) lander is used to observe the structure and dynamics of Earth's plasmasphere from the Moon. By detecting the resonance line emission of helium ions (He+) at 30.4 nm, the EUVC images the entire plasmasphere with a time resolution of 10 min and a spatial resolution of about 0.1 Earth radius (RE) in a single frame. We first present details about the data processing from EUVC and the data acquisition in the commissioning phase, and then report some initial results, which reflect the basic features of the plas- masphere well. The photon count and emission intensity of EUVC are consistent with previous observations and models, which indicate that the EUVC works normally and can provide high quality data for future studies.
文摘As one of the key units of space CCD camera,the temperature range and stability of CCD components affect the image's indexes.Reasonable thermal design and robust thermal control devices are needed.One kind of temperature control loop heat pipe(TCLHP) is designed,which highly meets the thermal control requirements of CCD components.In order to study the dynamic behaviors of heat and mass transfer of TCLHP,particularly in the orbital flight case,a transient numerical model is developed by using the well-established empirical correlations for flow models within three dimensional thermal modeling.The temperature control principle and details of mathematical model are presented.The model is used to study operating state,flow and heat characteristics based upon the analyses of variations of temperature,pressure and quality under different operating modes and external heat flux variations.The results indicate that TCLHP can satisfy the thermal control requirements of CCD components well,and always ensure good temperature stability and uniformity.By comparison between flight data and simulated results,it is found that the model is to be accurate to within 1℃.The model can be better used for predicting and understanding the transient performance of TCLHP.
基金supported by the National Natural Science Foundation of China(No.61205168)the National Science and Technology Support Program of China(No.2012BAH91F03)
文摘A method based on the XYZLMS interim connection space is proposed to accurately acquire the multi-spectral images by digital still cameras. The XYZLMS values are firstly predicted from RGB values by polynomial model with local training samples and then spectral reflectance is constructed from XYZLMS values by pseudo-inverse method. An experiment is implemented for multi-spectral image acquisition based on a commercial digital still camera. The results indicate that multi-spectral images can be accurately acquired except the very dark colors.
基金supported by the Fundamental Research Funds for the Central Universities (No. 2014QNA39)the Outstanding Young and Middle-Aged University Teachers and Presidents Training Abroad Project of Jiangsu Provincethe Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD)
文摘Incipient plasmonic bubble formation is observed around gold nanopillars with different inter-nanopillar separations. The experimental measurements and theoretical analysis show that the nanobubble formation is due to the enhanced plasmonic resonance rather than from the laser heating. Inter-nanopillar distribution may lead to threshold fluence variations. The lifetime of plasmonic bubbles can reach several minutes. Furthermore, both the radius and the growth rate of the plasmonic nanobubble increase as the inter-nanopillar distribution decreases.Smaller-spacing distributed arrays produced larger bubbles. The maximum growth rate of the bubbles can be reached at about 883.5 × 10^-6m∕s on 1 μm nanopillars, but it is only 56.9 × 10^-6m∕s on 4 μm nanopillars.