Patent ID: 6070128
Filing Date: 2000-05-30
Classification: B01J,G01N

Abstract:
A method of determining or predicting a value P.sub.x which is a value of a property of a material X or a property of a product of a process from said material or yield of said process, which method comprises measuring the absorption D.sub.ix of said material at more than one wavelength in the region 600-2600 nm, comparing said signals indicative of said absorptions or a mathematical function thereof with signals indicative of absorptions D.sub.i m at the same wavelengths or a mathematical function thereof for a number of standards S in a bank for which said property or yield P is known, and choosing from the bank at least one standard S.sub.m with property P.sub.m said standard having the smallest average value of the absolute difference at each wavelength i between the signal for the material and the signal for the standard S.sub.m to obtain P.sub.x, with averaging of said properties or yields P.sub.m when more than one standard S.sub.m is chosen.