Fig. 1: Scheme of the double echo modified z-Filter (DEMz) sequence as used in the current approach.
From: Development of a 31P magnetic resonance spectroscopy technique to quantify NADH and NAD+ at 3 T
After an initial adiabatic half passage hard pulse and two adiabatic full passage pulses, J-coupled α-ATP spins acquire a phase of 90° with respect to uncoupled spins at t = TEj = 1/2 J and end up aligned with x (t = TEj). At t90−x a non-selective 90° block pulse flips spins with J-coupling constants different from that of α-ATP about the x-axis back towards the z-axis. Spins remaining in the x–y plane are then dephased by GSpoil. A varying delay reduces potential phase distortions caused by zero quantum coherences (ZQC).
