Agriparticulate Reference Materials: Theory of the in situ Native Standard Method to Verify Particulate Burden in Cotton

Abstract

A fundamental approach is presented to verify the total particulate burden in cotton reference material. The method is founded on a null hypothesis. The hypothesis states that upon rendering a cotton free of foreign material, the recoverable particulate-lint ith property constant λ_i (for example, color) of the calibrated mixture is equal to that for the in situ particulate constant, ψ_i. Cotton is mechanically cleaned by cycling through a mechanical cleaner. Particulates recoverable from cleaning are added back to the cleaned lint, and the ith property is measured to facilitate computation of λ_i. Cleaned lint spiked with recoverable particulates constitutes a native standard. Assuming that λ_i = ψ_i, an apparent particulate concentration in the uncleaned material is computed by measuring the in situ property value. The spiking process is repeated, and different properties are measured. Means of apparent in situ partioulate levels as determined from various properties are measured. Means of apparent in situ particulate levels as determined from various properties are compared to decide which groups, if any, differ because of rejection of the null hypothesis. Particulate burden in the reference material is the average of the accepted group means. The method is demonstrated on ginned cotton.