The Experts below are selected from a list of 10908 Experts worldwide ranked by ideXlab platform
Zhaocheng Zeng - One of the best experts on this subject based on the ideXlab platform.
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remote sensing of angular Scattering Effect of aerosols in a north american megacity
Remote Sensing of Environment, 2020Co-Authors: Zhaocheng Zeng, Feng Xu, Vijay Natraj, Thomas J Pongetti, Runlie Shia, Qiong Zhang, Stanley P Sander, Yuk L YungAbstract:Abstract The angle-dependent Scattering Effect of aerosols in the atmosphere not only influences climate through radiative forcing Effects but also impacts trace gas remote sensing by modifying the path of radiation through the atmosphere. The aerosol phase function, which characterizes the angular signature of Scattering, has been continuously monitored from ground-based and space-borne observations. However, the range of Scattering angles these instruments can sample is very limited. Here, we report multi-year measurements from a mountain-top remote sensing instrument: the California Laboratory for Atmospheric Remote Sensing Fourier Transform Spectrometer (CLARS-FTS), which overlooks the Los Angeles megacity. The observational geometries of CLARS-FTS provide a wide range of Scattering angles, from about 20° (forward) to about 140° (backward), which is larger than the range provided by any existing aerosol remote sensing instrument. We then quantify the aerosol angular Scattering Effect using the O2 ratio, which is the ratio of retrieved O2 Slant Column Density (SCD) to geometric O2 SCD. The O2 ratio quantifies the light path modification due to aerosol Scattering, with a value of 1 representing an aerosol-free scenario. The lower the O2 ratio value than 1, the stronger the aerosol loading. CLARS-FTS measurements are highly sensitive to the angular Scattering Effect of aerosols in the Los Angeles (LA) urban atmosphere, due to the long light path going through the boundary layer and the wide range of observational angles. The differences in aerosol Scattering between different surface reflection points targeted by CLARS-FTS can be explained by differences in their angular Scattering geometries. The correlation between measurements at different targets can be used to quantify the strength of the angular dependence of the aerosol phase function. Applying the correlation technique to CLARS-FTS measurements, we find that, from 2011 to 2018, there is no significant trend in the aerosol phase function in the LA megacity. Overall, this study provides a practical observing strategy for quantifying the angular dependence of aerosol Scattering in urban atmospheres that could potentially contribute towards improved greenhouse gas remote sensing in megacities.
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remote sensing of angular Scattering Effect of aerosols in a north american megacity
arXiv: Atmospheric and Oceanic Physics, 2019Co-Authors: Zhaocheng Zeng, Feng Xu, Vijay Natraj, Thomas J Pongetti, Runlie Shia, Qiong Zhang, Stanley P Sander, Yuk L YungAbstract:The angle-dependent Scattering Effect of aerosols in the atmosphere can be used to infer their compositions, which in turn is important to understand their impacts of human health and Earth climate. The aerosol phase function, which characterizes the angular signature of Scattering, has been continuously monitored from ground-based and space-borne observations. However, the range of Scattering angles these instruments can sample is very limited. There is a dearth of research on the remote sensing of aerosol angular Scattering Effect at a city scale that analyzes diurnal variability and includes a wide range of Scattering angles. Here, we quantify the aerosol angular Scattering Effect using measurements from a mountain-top remote sensing instrument: the California Laboratory for Atmospheric Remote Sensing Fourier Transform Spectrometer (CLARS-FTS). CLARS-FTS is located on top of the Mt. Wilson (1.67km above sea level) overlooking the Los Angeles (LA) megacity and receives reflected sunlight from targeted surface reflection points. The observational geometries of CLARS-FTS provide a wide range of Scattering angles, from about 20 degrees (forward) to about 140 degrees (backward). The O2 ratio, which is the ratio of retrieved O2 Slant Column Density (SCD) to geometric O2 SCD, quantifies the aerosol transmission with a value of 1.0 represent aerosol-free and with a value closer to 0.0 represents stronger aerosol loadings. The aerosol transmission quantified by the O2 ratio from CLARS measurements provides an Effective indicator of the aerosol Scattering Effect.
Yuk L Yung - One of the best experts on this subject based on the ideXlab platform.
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remote sensing of angular Scattering Effect of aerosols in a north american megacity
Remote Sensing of Environment, 2020Co-Authors: Zhaocheng Zeng, Feng Xu, Vijay Natraj, Thomas J Pongetti, Runlie Shia, Qiong Zhang, Stanley P Sander, Yuk L YungAbstract:Abstract The angle-dependent Scattering Effect of aerosols in the atmosphere not only influences climate through radiative forcing Effects but also impacts trace gas remote sensing by modifying the path of radiation through the atmosphere. The aerosol phase function, which characterizes the angular signature of Scattering, has been continuously monitored from ground-based and space-borne observations. However, the range of Scattering angles these instruments can sample is very limited. Here, we report multi-year measurements from a mountain-top remote sensing instrument: the California Laboratory for Atmospheric Remote Sensing Fourier Transform Spectrometer (CLARS-FTS), which overlooks the Los Angeles megacity. The observational geometries of CLARS-FTS provide a wide range of Scattering angles, from about 20° (forward) to about 140° (backward), which is larger than the range provided by any existing aerosol remote sensing instrument. We then quantify the aerosol angular Scattering Effect using the O2 ratio, which is the ratio of retrieved O2 Slant Column Density (SCD) to geometric O2 SCD. The O2 ratio quantifies the light path modification due to aerosol Scattering, with a value of 1 representing an aerosol-free scenario. The lower the O2 ratio value than 1, the stronger the aerosol loading. CLARS-FTS measurements are highly sensitive to the angular Scattering Effect of aerosols in the Los Angeles (LA) urban atmosphere, due to the long light path going through the boundary layer and the wide range of observational angles. The differences in aerosol Scattering between different surface reflection points targeted by CLARS-FTS can be explained by differences in their angular Scattering geometries. The correlation between measurements at different targets can be used to quantify the strength of the angular dependence of the aerosol phase function. Applying the correlation technique to CLARS-FTS measurements, we find that, from 2011 to 2018, there is no significant trend in the aerosol phase function in the LA megacity. Overall, this study provides a practical observing strategy for quantifying the angular dependence of aerosol Scattering in urban atmospheres that could potentially contribute towards improved greenhouse gas remote sensing in megacities.
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remote sensing of angular Scattering Effect of aerosols in a north american megacity
arXiv: Atmospheric and Oceanic Physics, 2019Co-Authors: Zhaocheng Zeng, Feng Xu, Vijay Natraj, Thomas J Pongetti, Runlie Shia, Qiong Zhang, Stanley P Sander, Yuk L YungAbstract:The angle-dependent Scattering Effect of aerosols in the atmosphere can be used to infer their compositions, which in turn is important to understand their impacts of human health and Earth climate. The aerosol phase function, which characterizes the angular signature of Scattering, has been continuously monitored from ground-based and space-borne observations. However, the range of Scattering angles these instruments can sample is very limited. There is a dearth of research on the remote sensing of aerosol angular Scattering Effect at a city scale that analyzes diurnal variability and includes a wide range of Scattering angles. Here, we quantify the aerosol angular Scattering Effect using measurements from a mountain-top remote sensing instrument: the California Laboratory for Atmospheric Remote Sensing Fourier Transform Spectrometer (CLARS-FTS). CLARS-FTS is located on top of the Mt. Wilson (1.67km above sea level) overlooking the Los Angeles (LA) megacity and receives reflected sunlight from targeted surface reflection points. The observational geometries of CLARS-FTS provide a wide range of Scattering angles, from about 20 degrees (forward) to about 140 degrees (backward). The O2 ratio, which is the ratio of retrieved O2 Slant Column Density (SCD) to geometric O2 SCD, quantifies the aerosol transmission with a value of 1.0 represent aerosol-free and with a value closer to 0.0 represents stronger aerosol loadings. The aerosol transmission quantified by the O2 ratio from CLARS measurements provides an Effective indicator of the aerosol Scattering Effect.
Yong Tang - One of the best experts on this subject based on the ideXlab platform.
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Scattering Effect on Optical Performance of Quantum Dot White Light-Emitting Diodes Incorporating SiO₂ Nanoparticles
IEEE Journal of Quantum Electronics, 2020Co-Authors: Zong-tao Li, Jie-xin Li, Jia-sheng Li, Zi-hao Deng, Yue-hua Deng, Yong TangAbstract:The Scattering Effect plays an important role in improving the optical performance of the quantum dot (QD) white light-emitting diodes (LEDs). A majority of the previous studies have focused on the planar packaging structure only with respect to total internal reflection (TIR). In this study, SiO2 nanoparticles are incorporated into QD-silicone encapsulation of LEDs with semi-spherical lens packaging (SSLP) to exploit their Scattering Effect. The results show that the radiant efficacy (31.35%@100 mA) and luminous efficacy (87.56 lm/W@100 mA) of QD white LEDs can be optimized using SiO2 nanoparticle concentration (0.1 wt%) and that they increase by 5.04% and 11.08%, respectively, as compared to the conventional structure. A comprehensive ray-tracing simulation validates that the nanoparticles in the SSLP structure lead to severe loss of chip light. On the contrary, the fluorescence light increases due to the enhancement of conversion by QDs. The transmission electron microscopy images and the finite-difference time-domain simulation have been introduced to investigate the surface adsorption of SiO2 nanoparticle. This study indicates that SiO2 incorporation is an Effective method to improve the efficiency of QD white LEDs, and provides a better understanding on the Scattering Effect based on TIR, color conversion, and surface adsorption.
Feng Xu - One of the best experts on this subject based on the ideXlab platform.
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remote sensing of angular Scattering Effect of aerosols in a north american megacity
Remote Sensing of Environment, 2020Co-Authors: Zhaocheng Zeng, Feng Xu, Vijay Natraj, Thomas J Pongetti, Runlie Shia, Qiong Zhang, Stanley P Sander, Yuk L YungAbstract:Abstract The angle-dependent Scattering Effect of aerosols in the atmosphere not only influences climate through radiative forcing Effects but also impacts trace gas remote sensing by modifying the path of radiation through the atmosphere. The aerosol phase function, which characterizes the angular signature of Scattering, has been continuously monitored from ground-based and space-borne observations. However, the range of Scattering angles these instruments can sample is very limited. Here, we report multi-year measurements from a mountain-top remote sensing instrument: the California Laboratory for Atmospheric Remote Sensing Fourier Transform Spectrometer (CLARS-FTS), which overlooks the Los Angeles megacity. The observational geometries of CLARS-FTS provide a wide range of Scattering angles, from about 20° (forward) to about 140° (backward), which is larger than the range provided by any existing aerosol remote sensing instrument. We then quantify the aerosol angular Scattering Effect using the O2 ratio, which is the ratio of retrieved O2 Slant Column Density (SCD) to geometric O2 SCD. The O2 ratio quantifies the light path modification due to aerosol Scattering, with a value of 1 representing an aerosol-free scenario. The lower the O2 ratio value than 1, the stronger the aerosol loading. CLARS-FTS measurements are highly sensitive to the angular Scattering Effect of aerosols in the Los Angeles (LA) urban atmosphere, due to the long light path going through the boundary layer and the wide range of observational angles. The differences in aerosol Scattering between different surface reflection points targeted by CLARS-FTS can be explained by differences in their angular Scattering geometries. The correlation between measurements at different targets can be used to quantify the strength of the angular dependence of the aerosol phase function. Applying the correlation technique to CLARS-FTS measurements, we find that, from 2011 to 2018, there is no significant trend in the aerosol phase function in the LA megacity. Overall, this study provides a practical observing strategy for quantifying the angular dependence of aerosol Scattering in urban atmospheres that could potentially contribute towards improved greenhouse gas remote sensing in megacities.
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remote sensing of angular Scattering Effect of aerosols in a north american megacity
arXiv: Atmospheric and Oceanic Physics, 2019Co-Authors: Zhaocheng Zeng, Feng Xu, Vijay Natraj, Thomas J Pongetti, Runlie Shia, Qiong Zhang, Stanley P Sander, Yuk L YungAbstract:The angle-dependent Scattering Effect of aerosols in the atmosphere can be used to infer their compositions, which in turn is important to understand their impacts of human health and Earth climate. The aerosol phase function, which characterizes the angular signature of Scattering, has been continuously monitored from ground-based and space-borne observations. However, the range of Scattering angles these instruments can sample is very limited. There is a dearth of research on the remote sensing of aerosol angular Scattering Effect at a city scale that analyzes diurnal variability and includes a wide range of Scattering angles. Here, we quantify the aerosol angular Scattering Effect using measurements from a mountain-top remote sensing instrument: the California Laboratory for Atmospheric Remote Sensing Fourier Transform Spectrometer (CLARS-FTS). CLARS-FTS is located on top of the Mt. Wilson (1.67km above sea level) overlooking the Los Angeles (LA) megacity and receives reflected sunlight from targeted surface reflection points. The observational geometries of CLARS-FTS provide a wide range of Scattering angles, from about 20 degrees (forward) to about 140 degrees (backward). The O2 ratio, which is the ratio of retrieved O2 Slant Column Density (SCD) to geometric O2 SCD, quantifies the aerosol transmission with a value of 1.0 represent aerosol-free and with a value closer to 0.0 represents stronger aerosol loadings. The aerosol transmission quantified by the O2 ratio from CLARS measurements provides an Effective indicator of the aerosol Scattering Effect.
Stanley P Sander - One of the best experts on this subject based on the ideXlab platform.
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remote sensing of angular Scattering Effect of aerosols in a north american megacity
Remote Sensing of Environment, 2020Co-Authors: Zhaocheng Zeng, Feng Xu, Vijay Natraj, Thomas J Pongetti, Runlie Shia, Qiong Zhang, Stanley P Sander, Yuk L YungAbstract:Abstract The angle-dependent Scattering Effect of aerosols in the atmosphere not only influences climate through radiative forcing Effects but also impacts trace gas remote sensing by modifying the path of radiation through the atmosphere. The aerosol phase function, which characterizes the angular signature of Scattering, has been continuously monitored from ground-based and space-borne observations. However, the range of Scattering angles these instruments can sample is very limited. Here, we report multi-year measurements from a mountain-top remote sensing instrument: the California Laboratory for Atmospheric Remote Sensing Fourier Transform Spectrometer (CLARS-FTS), which overlooks the Los Angeles megacity. The observational geometries of CLARS-FTS provide a wide range of Scattering angles, from about 20° (forward) to about 140° (backward), which is larger than the range provided by any existing aerosol remote sensing instrument. We then quantify the aerosol angular Scattering Effect using the O2 ratio, which is the ratio of retrieved O2 Slant Column Density (SCD) to geometric O2 SCD. The O2 ratio quantifies the light path modification due to aerosol Scattering, with a value of 1 representing an aerosol-free scenario. The lower the O2 ratio value than 1, the stronger the aerosol loading. CLARS-FTS measurements are highly sensitive to the angular Scattering Effect of aerosols in the Los Angeles (LA) urban atmosphere, due to the long light path going through the boundary layer and the wide range of observational angles. The differences in aerosol Scattering between different surface reflection points targeted by CLARS-FTS can be explained by differences in their angular Scattering geometries. The correlation between measurements at different targets can be used to quantify the strength of the angular dependence of the aerosol phase function. Applying the correlation technique to CLARS-FTS measurements, we find that, from 2011 to 2018, there is no significant trend in the aerosol phase function in the LA megacity. Overall, this study provides a practical observing strategy for quantifying the angular dependence of aerosol Scattering in urban atmospheres that could potentially contribute towards improved greenhouse gas remote sensing in megacities.
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remote sensing of angular Scattering Effect of aerosols in a north american megacity
arXiv: Atmospheric and Oceanic Physics, 2019Co-Authors: Zhaocheng Zeng, Feng Xu, Vijay Natraj, Thomas J Pongetti, Runlie Shia, Qiong Zhang, Stanley P Sander, Yuk L YungAbstract:The angle-dependent Scattering Effect of aerosols in the atmosphere can be used to infer their compositions, which in turn is important to understand their impacts of human health and Earth climate. The aerosol phase function, which characterizes the angular signature of Scattering, has been continuously monitored from ground-based and space-borne observations. However, the range of Scattering angles these instruments can sample is very limited. There is a dearth of research on the remote sensing of aerosol angular Scattering Effect at a city scale that analyzes diurnal variability and includes a wide range of Scattering angles. Here, we quantify the aerosol angular Scattering Effect using measurements from a mountain-top remote sensing instrument: the California Laboratory for Atmospheric Remote Sensing Fourier Transform Spectrometer (CLARS-FTS). CLARS-FTS is located on top of the Mt. Wilson (1.67km above sea level) overlooking the Los Angeles (LA) megacity and receives reflected sunlight from targeted surface reflection points. The observational geometries of CLARS-FTS provide a wide range of Scattering angles, from about 20 degrees (forward) to about 140 degrees (backward). The O2 ratio, which is the ratio of retrieved O2 Slant Column Density (SCD) to geometric O2 SCD, quantifies the aerosol transmission with a value of 1.0 represent aerosol-free and with a value closer to 0.0 represents stronger aerosol loadings. The aerosol transmission quantified by the O2 ratio from CLARS measurements provides an Effective indicator of the aerosol Scattering Effect.
