SYSTEMS AND METHODS FOR PRESSURE DIFFERENTIAL MOLECULAR SPECTROSCOPY OF COMPRESSIBLE FLUIDS

摘要

Disclosed herein are spectroscopic analysis systems and methods for measuring and monitoring the chemical composition and / or impurity content of a sample or sample stream using absorption spectroscopy. Specifically, in certain embodiments, the present invention uses a sample pressure variation to change the magnitude of the received absorption spectrum (e.g., a wavelength dependent signal) for the sample, thereby eliminating the need for a reference or zero sample Lt; / RTI Rather than using a reference or zero sample, the embodiments described herein obtain a spectrum / signal from a sample-containing cell at both the first pressure and the second (different) pressure.