New mathematical model for investigating the sampling errors of two-component particulate mixtures

A new mathematical model was established for investigating the sampling of two-component particulate mixtures by mass. By the introduction of a new concept named as logical unit of sampling by mass, equations of estimating the standard deviation and relative standard deviation of sampling by mass were presented. The physical meaning of the logical unit of sampling by mass was also studied. These equations were verified by the sampling for chemical analysis of two-component medicine tablets. This theory is generally applicable so as to enrich the sampling theory of analytical chemistry and direct the sampling practices.