Determination of the Content of Astragaloside IV in Yikangshu Granules by High Performance Liquid Chromatography

[Objectives]The research aimed to establish a high performance liquid chromatography method for the content determination of astragaloside IV in Yikangshu Granules.[Methods]Kromasil 5μm C18(2),100 A,250 mm×4.6 mm was used;the mobile phase was acetonitrile-water(32∶68);flow velocity was 1.0 mL/min;the temperature of evaporator and sprayer was 80 and 30℃;the column temperature was set at 30℃,and injection volume was 20μL.[Results]Astragaloside IV showed a good linear relationship in the range of 1.01-10.14μg with the peak area,and regression equation was lgY=1.7728lgX+1.597(r=0.9999).The limit of detection for astragaloside IV was 1.96 ng,and the average recovery rate was 95.31%.[Conclusions]This method is sensitive,accurate and reproducible,with good linearity,and it is suitable for the content determination of astragaloside IV in health food Yikangshu Granules.

Determination of the Content of Gastrodin in Jingtianshenma Tablets by High Performance Liquid Chromatography

[Objectives]The research aimed to establish a high performance liquid chromatography method for the content determination of gastrodin in Jingtianshenma Tablets.[Methods]A phenomenex Luna C18(250 mm×4.6 mm,5μm)column was used;the mobile phase was acetonitrile-0.05%phosphoric acid solution(3∶97);the detection wavelength was 220 nm,and the column temperature was set at 25℃.[Results]Gastrodin showed a good linear relationship in the range of 0.0984-0.5904μg with the peak area,and regression equation was Y=2000000X-51999(r=0.9999).The limits of detection and quantification for gastrodin were 2.50 and 4.20 ng respectively,and the average recovery rate was 95.95%.[Conclusions]This method is sensitive,accurate and reproducible,with good linearity,and it is suitable for the content determination of gastrodin in health food Jingtianshenma Tablets.

Event-Triggered-Backstepping-Based Parallel Approaching Guidance Method for Maneuvering Target Interception

In order to achieve a straight ballistic trajectory of missile and reduce the update frequency of the missile normal acceleration for the interception of maneuvering target,a backstepping-based parallel approaching guidance method is designed with nonlinear disturbance observer(NDO)technique and event-triggered(ET)mechanism in this paper.In order to suppress the adverse e®ect of target maneuver,the NDO is designed to estimate the target maneuvering acceleration.Then,the NDO-based backstepping method is used to obtain the normal acceleration of missile and realize the parallel approaching guidance.In order to reduce the update frequency of missile normal acceleration,the ET mechanism is employed in the parallel approaching guidance method.If the missile trajectory is relatively straight,the normal acceleration of missile remains unchanged.On the contrary,if the missile trajectory is not straight,the normal acceleration of missile is updated to make the missile trajectory straight.In this way,the ET-based parallel approaching guidance can be obtained.Furthermore,a determined method for the initial missile°ight-path angle is proposed to keep the normal acceleration of missile at zero in the initial stage of interception.Besides,Lyapunov stability analysis method is used to prove that all signals in the closed-loop guidance system are uniformly ultimately bounded.Finally,simulation results show the e®ectiveness of the proposed guidance method.