Quantitative determination of pinoresinol diglucoside in Eucommiae unloads by NIRS Effect of Processing on the Contents of PinoresinolDiglucoside in Cortex Eucommiae Simultaneous determination of geniposidic acid, chlorogenic acid, geniposide,and pinoresinol diglucoside in Eucommia ulmoides by HPLC Simultaneous determination of four active compounds in Tiangou capsules by HPLC Simultaneous determination of geniposidic acid, chlorogenic acid, geniposide, and pinoresinol diglucoside in Eucommia ulmoides by HPLC Comparison on contents of four active constituents between slab and branch barks of Eucommia ulmoides