普通喷嘴喷出的水柱是直线型的,在普通喷嘴中加入倒U型和三角形结构,就能够使得喷嘴喷出来的水柱呈现振荡形式。利用多相流VOF(Volume of Fluid)模型模拟内建振荡结构的喷嘴的喷射流动过程,CFD仿真结果显示,喷嘴喷射的水柱呈现上下摆动...普通喷嘴喷出的水柱是直线型的,在普通喷嘴中加入倒U型和三角形结构,就能够使得喷嘴喷出来的水柱呈现振荡形式。利用多相流VOF(Volume of Fluid)模型模拟内建振荡结构的喷嘴的喷射流动过程,CFD仿真结果显示,喷嘴喷射的水柱呈现上下摆动的状态,和真实情况相吻合。展开更多
A reverse-phase HPLC method was developed for the simultaneous separation and determination of five bioactive phenolic acids,yunnaneic acid E,rosmarinic acid,lithospermic acid,salvianolic acid B and salvianolic acid A...A reverse-phase HPLC method was developed for the simultaneous separation and determination of five bioactive phenolic acids,yunnaneic acid E,rosmarinic acid,lithospermic acid,salvianolic acid B and salvianolic acid A in eight different samples of Salvia yunnanensis collected in Yunnan Province.For comparison,the sample of Salvia miltiorrhiza was included. All the samples were extracted for 60 min with 50%methanol in an ultrasonic bath.The optimal separation was achieved on a YMC-Pack Pro C18 column,with a gradient of 0.1%（v/v） phosphoric acid and acetonitrile,at a flow rate of 1.0 mL/min and at a detection wavelength of 280 nm.The separation was obtained within 65 min for five bioactive phenolic acids.All calibration curves showed good linearity（r^2〉0.999） within test ranges.The relative standard deviation of the method was less than 5%for intra- and inter-day assays.The mean recovery of the method was in the range from 97%to 104%,with RSD less than 5%.This assay was successfully applied to the quantitative determination of five bioactive phenolic acids in nine resource samples. The results showed that the developed HPLC assay was suitable for the quality control of S.yunnanensis and it can be used to differentiate S.yunnanensis from S.miltiorrhiza.展开更多
基金National High-Tech R & D Program(863 Program, Grant No.2004AA2Z3342)
文摘A reverse-phase HPLC method was developed for the simultaneous separation and determination of five bioactive phenolic acids,yunnaneic acid E,rosmarinic acid,lithospermic acid,salvianolic acid B and salvianolic acid A in eight different samples of Salvia yunnanensis collected in Yunnan Province.For comparison,the sample of Salvia miltiorrhiza was included. All the samples were extracted for 60 min with 50%methanol in an ultrasonic bath.The optimal separation was achieved on a YMC-Pack Pro C18 column,with a gradient of 0.1%（v/v） phosphoric acid and acetonitrile,at a flow rate of 1.0 mL/min and at a detection wavelength of 280 nm.The separation was obtained within 65 min for five bioactive phenolic acids.All calibration curves showed good linearity（r^2〉0.999） within test ranges.The relative standard deviation of the method was less than 5%for intra- and inter-day assays.The mean recovery of the method was in the range from 97%to 104%,with RSD less than 5%.This assay was successfully applied to the quantitative determination of five bioactive phenolic acids in nine resource samples. The results showed that the developed HPLC assay was suitable for the quality control of S.yunnanensis and it can be used to differentiate S.yunnanensis from S.miltiorrhiza.
