Chemical constituents from stems of Ficus auriculata Studies on the Chemical Constituents in the Bark of Ilicium jadifengpi B.N. Thermal Decomposition Reaction of Abietic Acid The Chemical Constituents in Dacrydium pierrei Theoretical Investigation on Structure and Property of Abietic Acids in Rosin A DFT Investigation on the Oxidation Reaction for the Unsaturated Bonds of Abietic Acid Acid Isomer Separation of Resin Acids in Rosin and Abietic Acid Molecular Structure Diterpenoids from Chinese Eaglewood