The separation and identification of the ephedrines(cathine,norephe-drine,ephedrine,pseudoephedrine,methylephedrine and ethylephedrine)and their derivatives obtained from TFAA,MSTFA,MSTFA+MBTFA and MSTFA+Ethyl acetate...The separation and identification of the ephedrines(cathine,norephe-drine,ephedrine,pseudoephedrine,methylephedrine and ethylephedrine)and their derivatives obtained from TFAA,MSTFA,MSTFA+MBTFA and MSTFA+Ethyl acetate deriva- tization were carried out by GC/MSD.展开更多
To determine the fatty acids in milk powders,the fatty oils of milk powders were extracted by Rose-Gettlieb method,the fatty acids in the fatty oils were esterified by potassium hydroxide-methanol,and then analyzed by...To determine the fatty acids in milk powders,the fatty oils of milk powders were extracted by Rose-Gettlieb method,the fatty acids in the fatty oils were esterified by potassium hydroxide-methanol,and then analyzed by gas chromatography-mass spectrometry (GC-MS).The results indicate that main fatty acids’ carbon chain were from 8 to 24,each fatty acid has different conents in different samples and the content was determined by area normalization.展开更多
文摘The separation and identification of the ephedrines(cathine,norephe-drine,ephedrine,pseudoephedrine,methylephedrine and ethylephedrine)and their derivatives obtained from TFAA,MSTFA,MSTFA+MBTFA and MSTFA+Ethyl acetate deriva- tization were carried out by GC/MSD.
文摘To determine the fatty acids in milk powders,the fatty oils of milk powders were extracted by Rose-Gettlieb method,the fatty acids in the fatty oils were esterified by potassium hydroxide-methanol,and then analyzed by gas chromatography-mass spectrometry (GC-MS).The results indicate that main fatty acids’ carbon chain were from 8 to 24,each fatty acid has different conents in different samples and the content was determined by area normalization.
