O484.5 9902113(?)用调制光反射方法测量薄膜的厚度=Measuremenof thin film thickness with modulated photoreflectancetechnique[刊,中]/郭元元,徐明华,张淑仪(南京大学声学研究所.江苏,南京(210093))∥南京大学学报·自然科学版...O484.5 9902113(?)用调制光反射方法测量薄膜的厚度=Measuremenof thin film thickness with modulated photoreflectancetechnique[刊,中]/郭元元,徐明华,张淑仪(南京大学声学研究所.江苏,南京(210093))∥南京大学学报·自然科学版.—1998,3(1).—79-84利用调制光反射技术对一系列不同厚度的二氧化硅薄膜进行了测量,在不同调制频率下检测样品的调制光反射相位信号,同时针对实验条件建立了三维理论模型,通过对实验曲线的最小方差拟合,推算出二氧化硅薄膜的厚度.图4参6(李瑞琴)展开更多
The ultra-small textured surface of multicrystalline silicon solar cell,prepared by electroless chemical-etching method,shows an excellent anti-reflection property over a wide spectral bandwidth.A novel back surface p...The ultra-small textured surface of multicrystalline silicon solar cell,prepared by electroless chemical-etching method,shows an excellent anti-reflection property over a wide spectral bandwidth.A novel back surface protection method and front surface passivation method have been used in the multicrystalline solar cells with ultra-small textured surfaces.With these improvements,the back surface remains intact after the etch process and the efficient minority lifetime is apparently increased.The test result shows that the solar cell with ultra-small textured surface can obtain better electrical performances by these improvements.展开更多
Soil salinization is a land degradation process that leads to reduced agricultural yields. This study investigated the method that can best predict electrical conductivity (EC) in dry soils using individual bands, a n...Soil salinization is a land degradation process that leads to reduced agricultural yields. This study investigated the method that can best predict electrical conductivity (EC) in dry soils using individual bands, a normalized difference salinity index (NDSI), partial least squares regression (PLSR), and bagging PLSR. Soil spectral reflectance of dried, ground, and sieved soil samples containing varying amounts of EC was measured using an ASD FieldSpec spectrometer in a darkroom. Predictive models were computed using a training dataset. An independent validation dataset was used to validate the models. The results showed that good predictions could be made based on bagging PLSR using first derivative reflectance (validation R2 = 0.85), PLSR using untransformed reflectance (validation R2 = 0.70), NDSI (validation R2 = 0.65), and the untransformed individual band at 2257 nm (validation R2 = 0.60) predictive models. These suggested the potential of mapping soil salinity using airborne and/or satellite hyperspectral data during dry seasons.展开更多
文摘O484.5 9902113(?)用调制光反射方法测量薄膜的厚度=Measuremenof thin film thickness with modulated photoreflectancetechnique[刊,中]/郭元元,徐明华,张淑仪(南京大学声学研究所.江苏,南京(210093))∥南京大学学报·自然科学版.—1998,3(1).—79-84利用调制光反射技术对一系列不同厚度的二氧化硅薄膜进行了测量,在不同调制频率下检测样品的调制光反射相位信号,同时针对实验条件建立了三维理论模型,通过对实验曲线的最小方差拟合,推算出二氧化硅薄膜的厚度.图4参6(李瑞琴)
基金supported by the National Basic Research Program of China("973" Project) (Grant No. 2009CB939703)the National Natural Science Foundation of China (Grant Nos. 11104319,51172268)the Chinese Academy of Solar Energy Action Plan and by Beijing Science and Technology Project (Grant No. Y2BK024001)
文摘The ultra-small textured surface of multicrystalline silicon solar cell,prepared by electroless chemical-etching method,shows an excellent anti-reflection property over a wide spectral bandwidth.A novel back surface protection method and front surface passivation method have been used in the multicrystalline solar cells with ultra-small textured surfaces.With these improvements,the back surface remains intact after the etch process and the efficient minority lifetime is apparently increased.The test result shows that the solar cell with ultra-small textured surface can obtain better electrical performances by these improvements.
基金Project supported by the Agricultural Research Council-Institute for Soil, Climate and Water (ARC-ISCW) of South Africa (No.GW51/072)the National Research Foundation (NRF) of South Africa (No.GW 51/083/01)the Water Research Commission (WRC)of South Africa (No.K5/1849)
文摘Soil salinization is a land degradation process that leads to reduced agricultural yields. This study investigated the method that can best predict electrical conductivity (EC) in dry soils using individual bands, a normalized difference salinity index (NDSI), partial least squares regression (PLSR), and bagging PLSR. Soil spectral reflectance of dried, ground, and sieved soil samples containing varying amounts of EC was measured using an ASD FieldSpec spectrometer in a darkroom. Predictive models were computed using a training dataset. An independent validation dataset was used to validate the models. The results showed that good predictions could be made based on bagging PLSR using first derivative reflectance (validation R2 = 0.85), PLSR using untransformed reflectance (validation R2 = 0.70), NDSI (validation R2 = 0.65), and the untransformed individual band at 2257 nm (validation R2 = 0.60) predictive models. These suggested the potential of mapping soil salinity using airborne and/or satellite hyperspectral data during dry seasons.
