The SEBAL (surface energy balance algorithm for land) model provides an efficient tool for estimating the spatial distribution of evapotranspiration, and performs a simple adjustment procedure to calculate sensible ...The SEBAL (surface energy balance algorithm for land) model provides an efficient tool for estimating the spatial distribution of evapotranspiration, and performs a simple adjustment procedure to calculate sensible heat flux using the wind speed data set from only one weather station. This paper proposes a simplified method to modify the traditional SEBAL model for calculating the 24-hour evapotranspiration ( ETduly ) in the Haihe Basin with data from 34 weather stations. We interpolated the wind speeds using the inverse distance weighting method to establish a wind field and then used it to calculate the friction velocity directly. This process also simplifies the iterative computation process of sensible heat flux. To validate the feasibility of this simplified method, we compared the results with those obtained with an appropriate but more complex method proposed by Tasumi, which separates a vast area into several sub-areas based on the weather conditions, and runs the SEBAL model separately in each sub-area. The results show good agreement between the evapotranspiration generated by the two methods, with a coefficient of determination (r2) of 0.966, which indicates the feasibility of estimating evapotranspiration over a large region with the simplified method.展开更多
Organic–inorganic hybrid perovskite solar cells,one of the most promising photovoltaic devices,have made great progress in their efficiency and preparation technology.In this study,uniform,highly conductive Li_(n)NiO...Organic–inorganic hybrid perovskite solar cells,one of the most promising photovoltaic devices,have made great progress in their efficiency and preparation technology.In this study,uniform,highly conductive Li_(n)NiO_(x)(0≤n≤1;0<x≤3)films were prepared by electrochemical deposition for a range of Li concentration.Photovoltaic performance for the perovskite solar cells was enhanced through incorporation of the ion pair of Ni^(3+)-Ni^(2+) as the interfacial passivation.Depending on the amount of lithium doping,controlled interfacial oxidation was induced by Ni^(3+).The Li_(0.32)NiO_(x)inhibited charge recombination,reduced the defect density,and enhanced the photocurrent density.A maximum power conversion efficiency of 20.44%was obtained by Li_(0.32)NiO_(x).Further,in the long-term,in-air stabilities of unencapsulated Li_(n)-NiO_(x) perovskite solar cells were demonstrated.展开更多
Dear Editor:Gastric cancer is a leading cause of cancer-related death.With the development and popularization of endoscopic techniques,early gastric cancer(EGC)is being diagnosed more frequently.EGC is a carcinoma tha...Dear Editor:Gastric cancer is a leading cause of cancer-related death.With the development and popularization of endoscopic techniques,early gastric cancer(EGC)is being diagnosed more frequently.EGC is a carcinoma that invades the submucosa regardless of the lymph node status.1 Endoscopic submucosal dissection(ESD)has been accepted as an optimal treatment for patients with EGC due to its low invasiveness and functional preservation.Guidelines indicate the curability of EGC after ESD based on the curative criteria.展开更多
基金supported by the National Natural Science Foundation of China (Grant No. 50809050)the Fundamental Research Funds for the Central Universities (Grant No. 2101024)
文摘The SEBAL (surface energy balance algorithm for land) model provides an efficient tool for estimating the spatial distribution of evapotranspiration, and performs a simple adjustment procedure to calculate sensible heat flux using the wind speed data set from only one weather station. This paper proposes a simplified method to modify the traditional SEBAL model for calculating the 24-hour evapotranspiration ( ETduly ) in the Haihe Basin with data from 34 weather stations. We interpolated the wind speeds using the inverse distance weighting method to establish a wind field and then used it to calculate the friction velocity directly. This process also simplifies the iterative computation process of sensible heat flux. To validate the feasibility of this simplified method, we compared the results with those obtained with an appropriate but more complex method proposed by Tasumi, which separates a vast area into several sub-areas based on the weather conditions, and runs the SEBAL model separately in each sub-area. The results show good agreement between the evapotranspiration generated by the two methods, with a coefficient of determination (r2) of 0.966, which indicates the feasibility of estimating evapotranspiration over a large region with the simplified method.
基金This work was financially supported by the National Natural Science Foundation of China(No.11772207)the Natural Science Foundation of Hebei Province(Nos.A2019210204 and E2019210292)+1 种基金the Special Project of Hebei Provincial Central Government Guiding Local Science and Technology Development(No.216Z4302G)the Youth Top-notch Talents Supporting Plan of Hebei Province and the support of State Key Laboratory of Mechanics and Control of Mechanical Structures,Nanjing University of Aeronautics and Astronautics(No.MCMS-E-0519G04).
文摘Organic–inorganic hybrid perovskite solar cells,one of the most promising photovoltaic devices,have made great progress in their efficiency and preparation technology.In this study,uniform,highly conductive Li_(n)NiO_(x)(0≤n≤1;0<x≤3)films were prepared by electrochemical deposition for a range of Li concentration.Photovoltaic performance for the perovskite solar cells was enhanced through incorporation of the ion pair of Ni^(3+)-Ni^(2+) as the interfacial passivation.Depending on the amount of lithium doping,controlled interfacial oxidation was induced by Ni^(3+).The Li_(0.32)NiO_(x)inhibited charge recombination,reduced the defect density,and enhanced the photocurrent density.A maximum power conversion efficiency of 20.44%was obtained by Li_(0.32)NiO_(x).Further,in the long-term,in-air stabilities of unencapsulated Li_(n)-NiO_(x) perovskite solar cells were demonstrated.
基金National Key Research and Development Program of China(No. 2017YFC0113600)。
文摘Dear Editor:Gastric cancer is a leading cause of cancer-related death.With the development and popularization of endoscopic techniques,early gastric cancer(EGC)is being diagnosed more frequently.EGC is a carcinoma that invades the submucosa regardless of the lymph node status.1 Endoscopic submucosal dissection(ESD)has been accepted as an optimal treatment for patients with EGC due to its low invasiveness and functional preservation.Guidelines indicate the curability of EGC after ESD based on the curative criteria.