Due to the high elevation, complex terrain, severe weather, and inaccessibility, direct meteorological observations do not exist over large portions of the Tibetan Plateau, especially the western part of it. Satellite...Due to the high elevation, complex terrain, severe weather, and inaccessibility, direct meteorological observations do not exist over large portions of the Tibetan Plateau, especially the western part of it. Satellite rainfall estimates have been very important sources for precipitation information, particularly in rain gauge-sparse regions. In this study, Tropical Rainfall Measuring Mission(TRMM) Multi-satellite Precipitation Analysis(TMPA) products 3B42, RTV5V6, and RTV7 were evaluated for their applicability to the upper Yellow and Yangtze River basins on the Tibetan Plateau. Moreover, the capability of the TMPA products to simulate streamflow was also investigated using the Variable Infiltration Capacity(VIC) semi-distributed hydrological model. Results show that 3B42 performs better than RTV5V6 and RTV7, based on verification of the China Meteorological Administration(CMA) observational precipitation data. RTV5V6 can roughly capture the spatial precipitation pattern but overestimation exists throughout the entire study region. The anticipated improvements of RTV7 relative to RTV5V6 have not been realized in this study. Our results suggest that RTV7 significantly overestimates the precipitation over the two river basins, though it can capture the seasonal cycle features of precipitation. 3B42 shows the best performance in streamflow simulation of the abovementioned satellite products. Although involved in gauge adjustment at a monthly scale, 3B42 is capable of daily streamflow simulation. RTV5V6 and RTV7 have no capability to simulate streamflow in the upper Yellow and Yangtze River basins.展开更多
Ga_(2)O_(3)has been regarded as a promising material for solar-blind detection due to its ultrawide bandgap and low growth cost.Although semiconductor microwires(MWs)possess unique optical and electronic characteristi...Ga_(2)O_(3)has been regarded as a promising material for solar-blind detection due to its ultrawide bandgap and low growth cost.Although semiconductor microwires(MWs)possess unique optical and electronic characteristics,the performances of photodetectors developed from Ga_(2)O_(3)MWs are still less than satisfactory.Herein,we demonstrate high-performance solar-blind photodetectors based on Sn-doped Ga_(2)O_(3)MWs,possessing a light/dark current ratio of 107 and a responsivity of 2,409 A/W at 40 V.Moreover,a 1×10 solar-blind photodetector linear array is developed based on the Sn-doped Ga_(2)O_(3)MWs via a patternedelectrodes method.And clear solar-blind images are obtained by using the photodetector array as the imaging unit of a solarblind imaging system.The results provide a convenient way to construct high-performance solar-blind photodetector arrays based on Ga_(2)O_(3)MWs,and thus may push forward their future applications.展开更多
Carbon/carbon(C/C) composites were deposited with graphite-like carbon(GLC) coating, and then, Arg-GlyAsp acid(RGD) peptides were successfully immobilized onto the functionalized GLC coating. GLC coating was utilized ...Carbon/carbon(C/C) composites were deposited with graphite-like carbon(GLC) coating, and then, Arg-GlyAsp acid(RGD) peptides were successfully immobilized onto the functionalized GLC coating. GLC coating was utilized to prevent carbon particles releasing and create a uniform surface condition for C/C composites. RGD peptides were utilized to improve biocompatibility of GLC coating. Surface chemical characterizations of functionalized GLC coating were detected by contact angle measurement, X-ray photoelectron spectroscopy and Raman spectra. Optical morphology of GLC coatings was observed by confocal laser scanning microscopy. In vitro biological performance was determined using samples seeded with MC3T3-E1 osteoblast-like cells and cultured for 1 week. Surface characterizations and morphological analysis indicated that C/C composites were covered by a dense and uniform GLC coating. Contact angle of GLC coating was reduced to 27.2° when it was functionalized by H_2O_2 oxidation at 40 °C for 1 h. In vitro cytological test showed that the RGD peptides immobilized GLC coating had a significant improvement in biocompatibility. It was suggested that RGD peptides provided GLC coating with a bioactive surface to improve cell adhesion and proliferation on C/C composites.展开更多
Lithium-air(Li-air)batteries have recently received much attention due to their extremely high theoretical energy densities.The significantly larger theoretical energy density of Li-air batteries is due to the use of ...Lithium-air(Li-air)batteries have recently received much attention due to their extremely high theoretical energy densities.The significantly larger theoretical energy density of Li-air batteries is due to the use of a pure lithium metal anode and the fact that the cathode oxidant,oxygen,is stored externally since it can be readily obtained from the surrounding air.However,before Li-air batteries can be realized as high-performance,commercially viable products there are still numerous scientific and technical challenges that must be overcome,from designing the cathode structure,to optimizing the electrolyte compositions and elucidating the complex chemical reactions that occur during charge and discharge.The scientific obstacles that are related to the performance of Li-air batteries open up an exciting opportunity for researchers from many different backgrounds to utilize their unique knowledge and skills to bridge the knowledge gaps that exist in current research projects.This review article is a summary of the most significant developments and challenges of practical Li-air batteries and the current understanding of their chemistry.展开更多
基金supported by the National Basic Research Program of China(the 973 Program,Grant No.2010CB951101)the Special Fund of the State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering of Hohai University(Grant No.1069-50985512)the"Strategic Priority Research Program"of the Chinese Academy of Sciences(Grant No.XDA05110102)
文摘Due to the high elevation, complex terrain, severe weather, and inaccessibility, direct meteorological observations do not exist over large portions of the Tibetan Plateau, especially the western part of it. Satellite rainfall estimates have been very important sources for precipitation information, particularly in rain gauge-sparse regions. In this study, Tropical Rainfall Measuring Mission(TRMM) Multi-satellite Precipitation Analysis(TMPA) products 3B42, RTV5V6, and RTV7 were evaluated for their applicability to the upper Yellow and Yangtze River basins on the Tibetan Plateau. Moreover, the capability of the TMPA products to simulate streamflow was also investigated using the Variable Infiltration Capacity(VIC) semi-distributed hydrological model. Results show that 3B42 performs better than RTV5V6 and RTV7, based on verification of the China Meteorological Administration(CMA) observational precipitation data. RTV5V6 can roughly capture the spatial precipitation pattern but overestimation exists throughout the entire study region. The anticipated improvements of RTV7 relative to RTV5V6 have not been realized in this study. Our results suggest that RTV7 significantly overestimates the precipitation over the two river basins, though it can capture the seasonal cycle features of precipitation. 3B42 shows the best performance in streamflow simulation of the abovementioned satellite products. Although involved in gauge adjustment at a monthly scale, 3B42 is capable of daily streamflow simulation. RTV5V6 and RTV7 have no capability to simulate streamflow in the upper Yellow and Yangtze River basins.
基金the National Natural Science Foundation of China(Nos.61804136,U1804155,and 62027816).
文摘Ga_(2)O_(3)has been regarded as a promising material for solar-blind detection due to its ultrawide bandgap and low growth cost.Although semiconductor microwires(MWs)possess unique optical and electronic characteristics,the performances of photodetectors developed from Ga_(2)O_(3)MWs are still less than satisfactory.Herein,we demonstrate high-performance solar-blind photodetectors based on Sn-doped Ga_(2)O_(3)MWs,possessing a light/dark current ratio of 107 and a responsivity of 2,409 A/W at 40 V.Moreover,a 1×10 solar-blind photodetector linear array is developed based on the Sn-doped Ga_(2)O_(3)MWs via a patternedelectrodes method.And clear solar-blind images are obtained by using the photodetector array as the imaging unit of a solarblind imaging system.The results provide a convenient way to construct high-performance solar-blind photodetector arrays based on Ga_(2)O_(3)MWs,and thus may push forward their future applications.
基金supported by the National Natural Science Foundation of China under Grant Nos.51202194 and 51221001the Programme of Introducing Talents of Discipline to Universities(‘‘111’’project of China)under Grant No.B08040
文摘Carbon/carbon(C/C) composites were deposited with graphite-like carbon(GLC) coating, and then, Arg-GlyAsp acid(RGD) peptides were successfully immobilized onto the functionalized GLC coating. GLC coating was utilized to prevent carbon particles releasing and create a uniform surface condition for C/C composites. RGD peptides were utilized to improve biocompatibility of GLC coating. Surface chemical characterizations of functionalized GLC coating were detected by contact angle measurement, X-ray photoelectron spectroscopy and Raman spectra. Optical morphology of GLC coatings was observed by confocal laser scanning microscopy. In vitro biological performance was determined using samples seeded with MC3T3-E1 osteoblast-like cells and cultured for 1 week. Surface characterizations and morphological analysis indicated that C/C composites were covered by a dense and uniform GLC coating. Contact angle of GLC coating was reduced to 27.2° when it was functionalized by H_2O_2 oxidation at 40 °C for 1 h. In vitro cytological test showed that the RGD peptides immobilized GLC coating had a significant improvement in biocompatibility. It was suggested that RGD peptides provided GLC coating with a bioactive surface to improve cell adhesion and proliferation on C/C composites.
基金supported by 100 Talents Programme of The Chinese Academy of Sciences,National Natural Science Foundation of China(Grant No.21101147)the Jilin Province Science and Technology Development Program(Grant No.20100102).
文摘Lithium-air(Li-air)batteries have recently received much attention due to their extremely high theoretical energy densities.The significantly larger theoretical energy density of Li-air batteries is due to the use of a pure lithium metal anode and the fact that the cathode oxidant,oxygen,is stored externally since it can be readily obtained from the surrounding air.However,before Li-air batteries can be realized as high-performance,commercially viable products there are still numerous scientific and technical challenges that must be overcome,from designing the cathode structure,to optimizing the electrolyte compositions and elucidating the complex chemical reactions that occur during charge and discharge.The scientific obstacles that are related to the performance of Li-air batteries open up an exciting opportunity for researchers from many different backgrounds to utilize their unique knowledge and skills to bridge the knowledge gaps that exist in current research projects.This review article is a summary of the most significant developments and challenges of practical Li-air batteries and the current understanding of their chemistry.
