The concentration of absorbable particulate matter less than 10 μm termed as PM10 is the most important urban air pollution index for air quality monitoring. This paper presents a space based PM10 monitoring algorith...The concentration of absorbable particulate matter less than 10 μm termed as PM10 is the most important urban air pollution index for air quality monitoring. This paper presents a space based PM10 monitoring algorithm based on QUAC （QUick atmosphere correction） for optical remote sensing data and SVR （support vector regression）. PM 10 concentration measurements from nine ground based stations in Hangzhou, China and the MODIS （moderate-resolution imaging spectroradiometer） images were analyzed. Experimental result indicates that the correlation between CD （correction differences） with actual measured data is better than correlation between AOD （aerosol optical depth） with measured data. In addition, the fitting performance of the SVR model established with CD and measured data is better than traditional regression models.展开更多
The enantioselective total synthesis of representative members of the eburnamine-vincamine alkaloids(+)-vincamine,(-)-eburnamonine,and(-)-criocerine has been accomplished.The synthesis took advantage of a highly stere...The enantioselective total synthesis of representative members of the eburnamine-vincamine alkaloids(+)-vincamine,(-)-eburnamonine,and(-)-criocerine has been accomplished.The synthesis took advantage of a highly stereoselective Ir-catalyzed hydrogenation/lactamization cascade reaction,which allows for the stereo-selective construction of the C/D rings as well as the installation of the critical cis-C20/C21 relative stereo-chemistry of the eburnamine-vincamine alkaloid skeleton in one pot.展开更多
文摘The concentration of absorbable particulate matter less than 10 μm termed as PM10 is the most important urban air pollution index for air quality monitoring. This paper presents a space based PM10 monitoring algorithm based on QUAC （QUick atmosphere correction） for optical remote sensing data and SVR （support vector regression）. PM 10 concentration measurements from nine ground based stations in Hangzhou, China and the MODIS （moderate-resolution imaging spectroradiometer） images were analyzed. Experimental result indicates that the correlation between CD （correction differences） with actual measured data is better than correlation between AOD （aerosol optical depth） with measured data. In addition, the fitting performance of the SVR model established with CD and measured data is better than traditional regression models.
基金support from the National Natural Science Foundation of China(No.U21A20278)the Sichuan Science and Technology Program(No.2021YJ0221).
文摘The enantioselective total synthesis of representative members of the eburnamine-vincamine alkaloids(+)-vincamine,(-)-eburnamonine,and(-)-criocerine has been accomplished.The synthesis took advantage of a highly stereoselective Ir-catalyzed hydrogenation/lactamization cascade reaction,which allows for the stereo-selective construction of the C/D rings as well as the installation of the critical cis-C20/C21 relative stereo-chemistry of the eburnamine-vincamine alkaloid skeleton in one pot.
