Nuclear acoustic resonance in fluids using piezoelectric nanoparticles

The influence of acoustic radiation in the form of ultrasound (US) on the nuclear magnetic resonance (NMR) signal of liquids in the presence of piezo- and ferroelectric nanoparticles was investigated. The NMR resonances of 1H and 23Na were influenced by US with a frequency of ωUS=18.26MHz. For hydrogen, US with a frequency ωUS=ω0 was used where ω0 is the Larmor frequency of 18.26MHz. For sodium, US with a frequency ωUS=2ω0,Na was used with ω0,Na=9.13MHz. A detailed description of nanoparticle properties and sample preparation is given. The influence of US on the spin–lattice relaxation time T1 was determined with an inversion recovery sequence for different concentrations of PZT. An elongation of T1 of 1H by 1.7% at a PZT concentration of 0.05% and an elongation of T1 of 23Na by 3% at a PZT concentration of 0.04% was observed. The elongation scales with the concentration of the PZT. An possible explanation of the effect of elongation is discussed.