Sample e.g. lubricant, analyzing method for e.g. uninterrupted fabrication process, involves analyzing part of fractions of sample by near-infrared spectroscopy by using near-infrared spectrometer operating in near infrared field

摘要

The method involves fractionating a sample by chromatography using a chromatograph (2) to obtain different fractions of the sample in a gaseous phase when the sample contains lightweight chemical compound and low molecular weight, where the sample is constituted of a petroleum product such as fuel. A part of the fractions of the sample is analyzed by near-infrared spectroscopy by using a near-infrared spectrometer (3) operating in a near infrared field. Independent claims are also included for the following: (1) a method for determining a characteristic specification such as cloud point and flash point, of a petroleum product (2) a device for analyzing a sample containing a set of chemical compounds and presenting an extended distribution of molecular weight.