Re: temperature calibration

jim breeyear (jbreeyea@zoo.uvm.edu)
Wed, 13 May 1998 10:49:41 -0400

I have use them a few times but we rely more on a thermocouple inserted
in a tube with a solvent which is lowered into the probe. The readout
can display up to .1 degrees. We have done calibrations down to 100
degree kelvin with pretty good repeatability. The readout goes a little
unstable at the freezing point of the solvent but after that it is ok.
The results seems to agree with what we expected. We have a Bruker ARX
500 narrow bore system.

Don Leek wrote:

> I need to do a variable temperature experiment where
> I know the temperature quite accurately. I have some
> charts from an old Bruker manual that give the chemical
> shifts of 100% methanol and 100% ethylene glycol versus
> temperature. Does anyone know how robust these calibrations
> are? In particular, is the calibration thrown off by a
> bit of moisture in the solvent, picked up from the air?
> I noticed that Wilmad sells sealed tubes of these
> solvents which they call chemical shift thermometers.
> Does this imply that one needs to take a lot of care
> when preparing these standards?
> Thanks
>
> ******************************************
> Donald M. Leek
> Steacie Institute for Molecular Sciences
> National Research Council Canada
> Ottawa, Canada K1A 0R6
> phone: (613) 993-6356
> fax: (613) 952-0068
> email: leek@ned1.sims.nrc.ca
> ******************************************

--


=+=+=+=+=+=+=+=+=+=+=+=+=+=+=
Jim Breeyear
Univ of Vermont
Manager, Inst.
Chemistry Dept.