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{{gam-pulse-sequence
|name=Doneshot
|synopsis=DOSY pulse sequence using bipolar gradient pairs
|family=[[Diffusion experiments]]
|dim=1
|macros=setup_dosy,makedosyparams
|author=gam,mn
|platform=Varian
|observe=H
}}
[[Category:DOSY]]
[[Category:Diffusion]]
[[Category:Oneshot]]
[[Category:PFG]]
[[Category:Wet]]
[[Category:Presat]]
[[Category:BPP]]
[[Category:Pulse sequence drawing]]

==Introduction==
The Oneshot sequence is suitable for "one-shot" acquisition (only one transient per gradient level), and is also a good general DOSY sequence. The pulse sequence is a more elaborated version of BPPSTE sequence, using [[BPP|bipolar pulse pairs]]. The refinements include a purge pulse in the diffusion delay, unbalanced gradient pulses in the bipolar pulse pairs as well as heating compensation gradients that are incremented as the diffusion gradients are incremented.

==The sequence==

<pulse title="The Oneshot sequence">
anchors:     @a0     @a1             @a2           @b0,b1            @c0,c1       @d0,d1              @e0                @f0            @g0,g1          @h0,h1              @x      @z
disp:       6@a0    2@a1            4@a2          2@b0              2@c0         2@d0                3@e0              20@f0           2@g0            2@h0                2@x    10@z
time: dummy  @a0    gstab @a1 d1     @a2   gstab   @b0     gstab     @c0   gstab  @d0       gstab     @e0     DELTAish   @f0     gstab  @g0      gstab  @h0  gstab                                 @x  aq @z
rf H:                                            90@b0            180@c0        90@d0                                                 90@g0          180@h0              acq@x-------z
pfg z:     g1@a0  g2@a1            g3@a2             g4@b1             g5@c1        g6@d1          g7@e0              g6@f0         g4@g1                 g5@h1  


rfchan H: label=^1H
pfgchan z: label=PFG

delay dummy: hide=true
delay gstab: hide=true
delay d1: label=d_1
delay DELTAish: hide=true

gradient g1: strength= 30 type=rectangular label=g
gradient g2: strength=-30 type=rectangular label=g
gradient g3: strength=-60 type=rectangular label=g
gradient g4: strength=100 type=rectangular label=g
gradient g5: strength=-80 type=rectangular label=g
gradient g6: strength=-20 type=rectangular label=g
gradient g7: strength= 60 type=rectangular label=g

gradient gx: strength= -10 type=rectangular label=g
</pulse>

==Macros==
====setup_dosy====
Enters a dialog to set-up the gradient array with equal steps in gradient squared. It is normally advisable to make even the first gradient level significant (e.g. 3G/cm)

====makedosparams====
Sets the parameter dosytimecubed <math>(\displaystyle \gamma^2 \displaystyle \delta^2  \displaystyle \Delta ') </math> when the pulse sequence is run. Dosytimecubed is a convenient parameter when fitting the data e.g. to produce a DOSY plot.

NB! These macros are compatible with VnmrJ2.3 or older.


==Software that can process DOSY data==
* The DOSY package of Vnmr and VnmrJ
{{#dpl: category=Software&DOSY}}
<font color="gray">'''Note:''' expand this list, by creating pages for programs and adding [[Organizing_pages_on_the_site#Categories|category links]] "Software" and "DOSY" to those pages.</font>

==RF parameters==
*'''pw''','''tpwr''','''tof''' - {{90}} pulse, its power level and transmitter offset
*'''satdly''','''satpwr''','''satfrq''' - length, power and offset of saturation pulse (used if '''satmode='y'''')

==Gradient parameters==
*'''gzlvl1''' - amplitude of diffusion encoding gradient
*'''kappa''' - unbalance factor for the bpp pulses. The default of 0.2 is almost always suitable
*'''gt1''' - total length of gradient encoding pulses gradient (split into two equal length bipolar pulses)
*'''gzlvl3''', '''gt3''' - amplitude and duration of the spoiler/purge gradient
*'''gzlvl_max''' - safety parameter, will trigger error message if gzlvl1*(1+kappa) > gzlvl_max

==Delays==
*'''del''' -  diffusion delay
*'''gstab''' - gradient recovery delay

==Flags==
*'''delflag''' - value ''''y'''' turns on the "diffusion" part of the pulse sequence, ''''n'''' - turns it into a one pulse 1D experiment
*'''wet''' - value ''''y'''' turns on [[Wet]] water suppression
*'''satmode''' - value ''''y'''' turns presaturation on

==References==
<biblio> 
#hammond02 bibtex=@article{pelta_one-shot_2002,
	title = {A one-shot sequence for high-resolution diffusion-ordered spectroscopy},
	volume = {40},
	url = {http://dx.doi.org/10.1002/mrc.1107},	
	number = {13},
	journal = {Magnetic Resonance in Chemistry},
	author = {Pelta, Michelle D. and Morris, Gareth A. and Stchedroff, Marc J. and Hammond, Stephen J.},
	year = {2002},
	pages = {S147--S152}
}
#hammond98 bibtex=@article{pelta_pulse_1998,
	title = {Pulse sequences for high-resolution diffusion-ordered spectroscopy (HR-DOSY)},
	volume = {36},
	url = {http://dx.doi.org/10.1002/(SICI)1097-458X(199810)36:10<706::AID-OMR363>3.0.CO;2-W},
	number = {10},
	journal = {Magnetic Resonance in Chemistry},
	author = {Pelta, Michelle D. and Barjat, Hervé  and Morris, Gareth A. and Davis, Adrian L. and Hammond, Stephen J.},
	year = {1998},
	pages = {706--714}
}

#bppste bibtex=@article{wu1995ido,
  title={{An improved diffusion-ordered spectroscopy experiment incorporating bipolar-gradient pulses}},
  author={Wu, DH and Chen, AD and Johnson, CS},
  journal={Journal of Magnetic Resonance, Series A},
  volume={115},
  number={2},
  pages={260--264},
  year={1995},
  publisher={Elsevier},
  url={http://dx.doi.org/10.1006/jmra.1995.1176}
}
</biblio>
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