The Essential Oil Analysis and Trace Element Study of the Roots of Piper nigrum L. A STUDY ON CHEMICAL CONSTITUENTS OF ESSENTIAL OIL FROM ABIES FARGESII FRANCH. LEAVES Analysis on chemical constituents of volatile oil in Magnolia officinalis var. biloba produced in Jinggangshan Determination of caryophyllene in Eupatorium fortune Determination of caryophyllene in Eupatorium fortune