Patent ID: 7868616
Filing Date: 2011-01-11
Classification: G01N,G01R,H01P

Abstract:
1. A method of using electron spin resonance spectrometry for in situ measuring of a degradation of operating machinery fluids, the method comprising acts of: passing a sample of a fluid through a resonating RF microwave cavity resonator during the application therethrough of a swept uniform magnetic field; wherein the fluid sample has a magnetic susceptibility and application of the swept uniform magnetic field causes a magnetic resonance that effects changes in the magnetic susceptibility of the sample at a RF frequency depending on a Zeeman field at the sample, modulating a modulation magnetic field, correspondingly to vary the magnetic susceptibility and the magnetic resonance in the fluid sample, which results in at least one of an RF phase modulation and an amplitude modulation; and measuring at least one of the resulting RF phase modulation or amplitude modulation thereof to derive an electron spin resonance signal, whereby the electron spin resonance signal is indicative of molecular changes in the fluid sample resulting from fluid degradation during operation of the machinery.