The prediction of the peak width at half height is an important aspect in the optimization of the chromatographic operating conditions.In this paper,a linear relationship,between the peak widths at half height and the...The prediction of the peak width at half height is an important aspect in the optimization of the chromatographic operating conditions.In this paper,a linear relationship,between the peak widths at half height and the retention values with various isocratic elution is observed.In gradient elution,however,the relationship between the peak widths at half height and the so-called invented retention values that correspond to the mobile phase composition by eluting the solute from the column end is developed.We believe that there is almost the same band width at half height inside the column (in unit of length)for different solutes.The peak width at half height in the chromatogram(in unit of time)is mainly determined by the capacity factor of the solute when it is eluted front the column end.The larger the capacity factor of a solute eluted from the column end,the more slowly will be the solute eluted from the column end and the wider will be the peak width at half height.It is possible to predict the peak width at half height in various isocratic and gradient elutions by using this linear relationship.展开更多
For modern stealth aircraft,it is important to analyze the influence of Radar Cross Section(RCS)peak exposure on penetration for guiding stealth design and penetration trajectory planning,which needs to reflect the RC...For modern stealth aircraft,it is important to analyze the influence of Radar Cross Section(RCS)peak exposure on penetration for guiding stealth design and penetration trajectory planning,which needs to reflect the RCS statistical uncertainty and the RCS difference with the change of incident angle.Based on the RCS characteristics of typical stealth aircraft,this paper established a simplified RCS dynamic fluctuation statistical model with the parameters log mean and log standard deviation.According to the detection probability algorithm in radar signal processing field,this paper built the algorithm of radar detection probability based on the RCS dynamic fluctuation statistical model.The analysis of examples concluded that the key to successful penetration is to shorten the RCS peak exposure time,which can be reduced by decreasing the RCS peak width or increasing velocity.Based on the conclusion,this paper proposed the method of turning maneuvering to reduce RCS peak exposure time dramatically.展开更多
基金This work was supported by the Foundation of Chinese Academy of Sciences.
文摘The prediction of the peak width at half height is an important aspect in the optimization of the chromatographic operating conditions.In this paper,a linear relationship,between the peak widths at half height and the retention values with various isocratic elution is observed.In gradient elution,however,the relationship between the peak widths at half height and the so-called invented retention values that correspond to the mobile phase composition by eluting the solute from the column end is developed.We believe that there is almost the same band width at half height inside the column (in unit of length)for different solutes.The peak width at half height in the chromatogram(in unit of time)is mainly determined by the capacity factor of the solute when it is eluted front the column end.The larger the capacity factor of a solute eluted from the column end,the more slowly will be the solute eluted from the column end and the wider will be the peak width at half height.It is possible to predict the peak width at half height in various isocratic and gradient elutions by using this linear relationship.
文摘For modern stealth aircraft,it is important to analyze the influence of Radar Cross Section(RCS)peak exposure on penetration for guiding stealth design and penetration trajectory planning,which needs to reflect the RCS statistical uncertainty and the RCS difference with the change of incident angle.Based on the RCS characteristics of typical stealth aircraft,this paper established a simplified RCS dynamic fluctuation statistical model with the parameters log mean and log standard deviation.According to the detection probability algorithm in radar signal processing field,this paper built the algorithm of radar detection probability based on the RCS dynamic fluctuation statistical model.The analysis of examples concluded that the key to successful penetration is to shorten the RCS peak exposure time,which can be reduced by decreasing the RCS peak width or increasing velocity.Based on the conclusion,this paper proposed the method of turning maneuvering to reduce RCS peak exposure time dramatically.
