The backward interval partial least squares(Bi PLS)and the synergy interval partial least squares(Si PLS)were applied to select the characteristic spectral regions representing the germination rate of 84 wheat seeds a...The backward interval partial least squares(Bi PLS)and the synergy interval partial least squares(Si PLS)were applied to select the characteristic spectral regions representing the germination rate of 84 wheat seeds and build the near infrared(NIR)quantitative analysis model of wheat seed germination rate.Results from comparison showed that the models built by two variable selection methods had better predictive ability than full-spectral partial least squares(PLS)model.The optimal model was obtained by Si PLS with the calibration and prediction correlation coefficient(R)at 0.902 and 0.967 respectively,and ratio of performance to standard deviate(RPD)at 3.75.Based on this,the physical chemistry significance of characteristic spectral regions was analyzed.The characteristic spectral of wheat seed germination rate contained characteristic peaks of water,protein,starch,fiber,which were the internal nutrients of the seed that influence the germination ability,thus explaining the mechanism of measuring wheat seed germination rate using NIR to a certain extent.展开更多
A convenient and large-scale preparation of retinoic acid 1 from β-ionone in five steps with 38% overall yield is described. The key steps are the epoxidization of 2 with a new methylated agent and the condensation ...A convenient and large-scale preparation of retinoic acid 1 from β-ionone in five steps with 38% overall yield is described. The key steps are the epoxidization of 2 with a new methylated agent and the condensation 4 with tetraethyl methylenediphophonate in one-pot procedure to prepare 6.展开更多
基金Opening Fund of State Key Laboratory of Soil Plant Machinery System Technology(2014-SKL-05)Natural and Social Science Foundation Cultivation Project of Beijing Technology and Business University(2015-19008001110)Graduate Student Scientific Research Capacity Promotion Project of Beijing Technology and Business University(2015)
文摘The backward interval partial least squares(Bi PLS)and the synergy interval partial least squares(Si PLS)were applied to select the characteristic spectral regions representing the germination rate of 84 wheat seeds and build the near infrared(NIR)quantitative analysis model of wheat seed germination rate.Results from comparison showed that the models built by two variable selection methods had better predictive ability than full-spectral partial least squares(PLS)model.The optimal model was obtained by Si PLS with the calibration and prediction correlation coefficient(R)at 0.902 and 0.967 respectively,and ratio of performance to standard deviate(RPD)at 3.75.Based on this,the physical chemistry significance of characteristic spectral regions was analyzed.The characteristic spectral of wheat seed germination rate contained characteristic peaks of water,protein,starch,fiber,which were the internal nutrients of the seed that influence the germination ability,thus explaining the mechanism of measuring wheat seed germination rate using NIR to a certain extent.
文摘A convenient and large-scale preparation of retinoic acid 1 from β-ionone in five steps with 38% overall yield is described. The key steps are the epoxidization of 2 with a new methylated agent and the condensation 4 with tetraethyl methylenediphophonate in one-pot procedure to prepare 6.
