Preparative method of tectoridin from rhizome of Iris tectorum Research on Simulated Moving Bed Chromatography Purification of Dextrose Mother Liquid Separation of dehydrocavidine from Corydalis saxicola by preparative chromatography Preparation of naringin and neohesperidin reference substances from Citrus aurantium by medium-low-pressure preparative chromatography Preparation technology of isochlorogenic acids A, B, and C