Standardization of near-infrared transmittance instruments

摘要

Three major aspects of NIR instrument standardization were studied: selection of standardization method, master instrument selection, and identification of important engineering parameters that influence master-slave differences. A set of 285 fixed filter instruments was used to test and evaluate standardization techniques as well as to determine the influence of selected engineering parameters;A newly designed standardization method based on the Wiener filter algorithm improved spectral as well as calibration transfer. While this method scored equally well in the spectral transfer in comparison to the currently used linear regression, it did not outperform the current method in calibration transfer;The influence of the master selection on the transfer of the calibration as well as spectral transfer was important. A designed master selection method proved to be successful for all but one measured case in which the reversed results showed high calibration dependency on the standardization procedure;Among the most significant factors influencing instrument spectral intensity differences were preamplifier and amplifier gain settings and filter response area and bandwidth.