On Wed, 20 Jun 2001, RAINER HAESSNER wrote:
> Hi all,
> for NOE measurements we use the common freeze-pump-thaw
> technique. For this purpose we always prepared special
> tubes by our glass blower. A little bit expensive, of course.
> Wilmad has ready prepared constricted tubes. Unfortunately
> I am not completely sure, how to attach these tubes to our
> vacuum pump. Even our local Wilmad dealer had no final
> idea.
> How do you do this job to prepare sealed tubes?
I have used a thermometer adapter for 14/20 glassware to attach the tube
to the pump using standard glassware. It makes a decent vacuum seal.
Now, sealing the tube with the adapter attached is tricky... You will
require a sharp flame and aluminum foil to insulate the heat from the
plastic of the adapter.
--
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Eugenio Alvarado Tel: 207-4106
Escuela de Quimica
Universidad de Costa Rica
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Received on Wed Jun 20 2001 - 17:29:08 MST