I was fiddling around in analysis trying to get a feel for things.
I put in a set of 5 spectra from a T2 series and did a rate analysis
that went fine.
Then I went into the Follow Shift Changes dialog to take a look at what
that did (obviously not a typical set of data to put into it but it
seemed to immediately be offering to calculate shift changes as a
function of delay time so I thought I would carry on. So I tried it and
seem to get strange results. According to the graphs (one is shown) the
shift changes of all peaks seem to be monotonically increasing with
delay time (so I thought maybe there is a temperature effect in the
pulse program). But if I look at the raw shifts reported in the peak
selection table the evidence is for a much more chaotic variation.
A screenshot is attached. What is going on ? Is there a difference
between the crosspeak positions reported in the peak selection table and
those used for the shift change calculations ? Am I misinterpreting what
is being shown ? Is there a help page for this popup - I could not find one.
(When I did group peaks it told me that "Experiments in series do not
have individual shift lists. Link each experiment to its own shift list
?". I usually said "no", but also go the same result if I say "yes").
Cheers
Jeremy
--
*********************************************************************************
Dr C. Jeremy Craven
Department of Molecular Biology and Biotechnology
University of Sheffield,
Firth Court, Western Bank
S10 2TN Sheffield UK
e-mail: [log in to unmask]
http://www.nmr.group.shef.ac.uk/CJC.html
Phone: x24323
From outside Sheffield: 0114 222 4323
From outside UK: +44 114 2224323
Fax: 0114 272 2800
*********************************************************************************
|