Hello All,
I know the preference is to weed out and toss chipped NMR tubes but it
seems tough to convince some chemists that they need to throw out an NMR
tube with a small chip and I do sympathize with the tight funding
environment we live in.
At my previous academic position there was a small cut-off wheel to clean
up the tops of the tubes. I was always a little leery of that since I
figured it might induce a lot of stress (i.e. weaken the tube) and that it
would leave an edge with tiny chips. It seemed that the cutoff should be
followed with a very quick flaming to smooth the cut. I also suspect that
it would take a long time to recoup the costs of a wet cut-off tool.
I am wondering if NMR labs are using cut-off wheels or just pushing for
tossing chipped tubes? I fully understand that chips weaken glass by
creating stress concentration points but I have yet to see a chip in an NMR
tube propagate to the spinner or below.
I am interest in a few answers if you can spare the time.
1) Are you using a glass cut-off wheel or allowing that option?
2) If you do use one please let me know the manufacture and the model
number.
2) Do you do any secondary operations such as a quick flaming?
3) Have you ever seen a small chip at the top of the tube lead to a tube
breaking in the magnet? (I understand this might be a hard one to pin down)
I can summarize the answers if that is of interest to this group.
Thanks for any answers!
Regards,
Joe
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Joe Dumais, Ph.D.
Associate Research Professor/Nuclear Magnetic Resonance Spectroscopist
Boise State University
College of Arts and Sciences
Department of Chemistry and Biochemistry
1910 University Drive, Boise, Idaho 83725-1520
(208) 426 4913
http://chemistry.boisestate.edu/
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Sent from an MS Windows PC
Received on Thu Apr 14 2016 - 13:23:22 MST