The structures and compositions of the purified petroleum acids were characterized by using infra-red spectrum, nuclear magnetic resonance and negative-ion electrospray ionization massspectrum.
通过红外光谱、核磁共振和负离子电喷雾质谱三种表征技术鉴定了原油中的石油酸结构和组成。
2
A new method for determination of melamine in milk powder and milk products by gas chromatography-massspectrum with selected ion monitor(GC-MS/SIM) was established in this paper.