Optimization of extraction technology for salidroside, tyrosol, crenulatin and gallic acid in Rhodiolae Crenulatae Radix et Rhizoma with orthogonal test Preliminary study on effect of Rhodiolae Crenulatae Radix et Rhizoma cell wall-broken decoction pieces on intestinal flora of mice Study on process and principle of lactose grinding modification to decrease hygroscopic of Rhodiolae Crenulatae Radix et Rhizoma extract Purification technology of salidroside by microporous adsorption resin