Pulsed NMR spectrometer with dynamic nuclear polarization for weak magnetic fields

Abstract

© Kazan Federal University (KFU)*. Pulsed nuclear magnetic resonance (NMR) spectrometer operating in weak magnetic field (~100 Oe) with the dynamic nuclear polarization (DNP) is described. The spectrometer is designed to study the Overhauser DNP effect in natural hydrocarbons for potential using DNP techniques to enhance the1 H NMR signal in crude oil and petroleum products. The unit was tested on a sample of the ethylene glycol chromium complex at room temperature. A DNP enhancement of ε = −50 for1 H NMR signal from solvent protons by pumping52 Cr5+ electronic transitions with the optimized pumping parameters was achieved.