Double monochromator methods

A small, compact spectroradiometer is less accurate than its much larger and more expensive, double-monochromator counterparts. The question to be asked is whether the increased accuracy is really needed or are the smaller units sufficient for our purposes. These smaller units are deemed more accurate because they produce both qualitative and quantitative data at the same instant. These items are important to pharmaceutical photostability testing. As noted in Chapter 3 of this book, current dosage measurements are inaccurate if performed according to the current ICH specified methods of dosage measurement. 

X-ray powder diffraction spectra were obtained on a CGR Theta 60 instrument using CuKa monochromated radiation (X. = 1.54 A). Unit cell parameters have been calculated by a double-refinement method. 

Optical characteristics of the obtained colloidal solution containing nanocomposites were analyzed by the method of optical absorption, with spectral range from 200 to 700 nm, on a spectrophotometer SF-46 with automatic data processing system. For registration Raman spectra was used system KSVU-23 with double monochromator. The structure and composition of the solid phase colloidal solution prepared by centrifugation... 

The intercomparison between the double Brewer monochromator and the Bentham DTI 50, assured the high quality of the measured UV-irradiances and also resulted to a new method for the correction of the global UV irradiance recorder by the Brewer for its angular response error [14],... 

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