Mass spectra (MS) of cholesterol esters and halides were obtained by means of Electron Impact (EI), Field Desorption (FD) and Chemical Ionization (CI).
研究了胆甾醇酯类和胆甾醇卤代物的电子轰击电离（EI）、场解吸电离（FD）、化学电离（CI）的质谱。
2
The oligomer structure in polycarbonate(PC)was studied by combination of GC-MS and FD-MS in the ethanol extract of PC.