A problem of one of our PhD-students:
To perform a series of off-resonance T1ro experiments she made a series
of pulse sequences, using a spin lock pulse on nitrogen with different
lengths. Simultanously she gives 180 pulses on protons and programmed
that as follows:
"d7 = 4m"
"d8 = 2.5m -0.5*p2"
"d9 = 2*d8"
(d7 d8 p2 d9 p2 d9 p2 d9 p2 d8 d7) (p6:sp6 ph6):f3
The spin-lock pulse has a shape that starts with a ramp of 4ms followed
by the spin-lock part (which can has different lengths in the different
shapes) and ends with a ramp of 4ms. In the example above p6 would be
28ms. That looks fine so far - and it works. But as the pulse length p6
increases the number of pulses and delays on proton increases. It works
fine upto SL lenghts of 100ms. But when arriving at a SL length of 150ms
(p6 = 158ms) the pulse sequence doesn't work any more and the following
message is shown:
'Error: duration out of range'
The spin lock part in that case looks as follows:
(d7 d8 p2 d9 p2 d9 p2 d9 p2 d9 p2 d9 p2 d9 p2 d9 p2 d9 p2 d9 p2
d9 p2 d9 p2 d9 p2 d9 p2 d9 p2 d9 p2 d9 p2 d9 p2 d9 p2 d9 p2 d9 p2 d9 p2
d9 p2 d9 p2 d9 p2 d9 p2 d9 p2 d9 p2 d9 p2 d9 p2 d8 d7) (p6:sp6 ph26):f3
Now the strange thing: We have two 600 consoles with practically
identical hard- and software on it. On one machine it used to run, the
other now refuses...! My first guess was a problem with memoryspace, but
the error-message does not really support this. Has anybody tried
something similar? Any suggestions of what's the problem here? Are there
protection parameters which constrain pulselengths? If yes, where can
they be found?
Thank you very much!
Best regards, Rainer
Groetjes,
Rainer
_v_
|o o|
************uuu**o**uuu*********************************************
Dr. Rainer Wechselberger
European NMR Large Scale Facility
Bijvoet Center for Biomolecular Research
Dept. of NMR Spectroscopy
Utrecht University
Padualaan 8
NL-3584 CH Utrecht
The Netherlands
phone: (++31)-(+30)-253-3295
fax: (++31)-(+30)-253-7623
mailto:wechselberger@nmr.chem.uu.nl
http://www.nmr.chem.ruu.nl/users/rainer/rainer.html
http://www.nmr.chem.ruu.nl/SON_lsf/SONNMRhome.html
********************************************************************
This archive was generated by hypermail 2b29 : Sun Dec 31 2000 - 01:15:02 PST