Peculiarity of the Nuclear Magnetic Resonance Method Application for the Liquid Medium Flow Parameters Control

Resumo

The new peculiarities that arise when using nuclear magnetic resonance (NMR) method for liquid medium stream control are identified and investigated. Signal/noise ratio can be increased fivefold when these peculiarities are taken into account in design of NMR spectrometers. It made it possible first time ever to register NMR absorption spectra from different flowing media and to determine relative concentrations of paramagnetic ions by using these spectra. The increase of signal/noise ratio also allowed measuring longitudinal T₁ and transverse T₂ relaxation times in flowing media with error rate that does not exceed 0.5%, while in previous NMR spectrometer designs T₁ and T₂ measurement error rates were greater than 1.0%. The simultaneous use of the absorption spectra and the measured values of the relaxation constants T₁ and T₂ allows eliminating errors completely when determining flowing medium condition. This is especially important when working with medical suspensions and biological solutions. The results of the experimental investigations of liquid media flows are presented below.