https://www.selleckchem.com/pr....oducts/caspofungin-a
Preheating of samples can induce significant nitrogen loss and δ N shift. Heating of samples above their optimal temperatures may cause nitrogen re-assimilation by the residual mineral or rock. Each mineral or rock has a characteristic optimal temperature and duration for complete nitrogen release. Preheating, under-heating or over-heating can cause nitrogen loss and isotopic shift. Therefore, we recommend using the offline combustion techniques and the optimal combustion conditions obtained in this study for nitrogen quanti