Refractometric analysis esp. of liq. - by small number of measuring cycles in differential measuring cell

摘要

Material (esp. liq.) analysis, by measuring beam refraction produced in a differential measuring cell, involves (a) detecting position-dependent intensity values (Ai) in the refraction direction in successive steps of (i) summation of all the measured intensity values (Ai) to determine a total intensity (S) and thus partial intensities (S/2 and S/t, t = greater than 2) as upper limit values; and (ii) summation of the position-dependent intensity values (Ai) to form partial sums (S(h-1) and S(k-1)) having position characterising indices (i=h and i=k) such that the associated intensity values (Ah and Ak) increase the partial sums (S(h-1) and S(k-1)) to above the respective limit values (S/t and S/2); and (b) determining a diffraction value as a photo-metric mean (M), a scattering value (Wt) and a transmission value (T) from the intensities determined in steps (i) and (ii) and from depicted measurement widths (b) in the refraction direction. USE/ADVANTAGE - The process is esp,. useful for analysis of liqs. when turbidity changes are caused by dirt particles and/or light transmission variations occur during sample flow through the differential measuring cell. The number of interrogation cycles, required for high resolution, is small even when several parameters are to be determined and thus increased current sample information content is obtained.