“…Finally, the API mass fractions (w API ) were calculated using the mass balance approach (equation 6) w API = 100 -Sw org,i -Sw inorg,i -Sw vol,i (6) where w API is the API mass fraction of each CRM expressed in g per 100 g, and Sw org,i , Sw inorg,i , Sw vol,i are the sums of mass fractions of organic, inorganic, and volatiles, respectively, also expressed in g per 100 g. The API mass fraction determined according to the mass balance approach was cross-checked by differential scanning calorimetry (DSC).…”