DOSY Experiments - Emory University

4.2.3 The “Doneshot” Experiment
Reference: M. D. Pelta, G. A. Morris, M. J. Tschedroff and S. J. Hammond: MRC 40, 147-152
(2002)
For eliminating radiation damping: M. A. Conell, A. L. Davis, A. M. Kenwright and G. A. Morris:
Anal. Bioanal. Chem. 378, 1568-1573, (2004).
Parameters:
'y' runs the Doneshot sequence
delflag
'n' runs the normal s2pul sequence
del the actual diffusion delay
gt1 total diffusion-encoding pulse strength
gzlvl1 diffusion-encoding pulse strength
gstab gradient stabilization delay (~0.0002-0.0003 s)
gt3 spoiling gradient duration (in seconds)
gzlvl3
spoiling gradient strength (destroys transverse magnetization
during the diffusion delay)
gzlvl_max
kappa
GRD
startflip
maximum accepted gradient strength 32767 with Performa II or IV,
2047 with Performa I
unbalancing factor between bipolar pulses as a proportion of
gradient strength (~0.2)
flip angle of the first pulse to eliminate radiation damping for very
concentrated samples labeled by θ on the pulse sequence above
alt_grd flag to invert gradient sign on alternate scans (default='n')
lkgate_flg flag to gate the lock sampling off during gradient pulses (default='n')
sspul flag for a GRD-90-GRD homospoil block
gzlvlhs gradient level for sspul
hsgt gradient duration for sspul
satmode
θ
„Dummy“ heating gradients Phase encoding gradients
Spoiler gradient Lock refocusing gradient
flag for optional solvent presaturation 'ynn' - does presat during
satdly 'yyn' - does presat during satdly and the diffusion delay
satdly presaturation delay before the sequence (part of d1)
satpwr
saturation power level
26
del