John A. Anderson wrote:
> -------------------------------------------------------------------
> John A. (Art) Anderson, Ph.D. http://www.rrc.uic.edu
> Spectroscopist Spectroscopy Facility
> voice: 312-996-6640 Research Resources Center (M/C 937)
> fax: 312-996-0539 The University of Illinois at Chicago
> email: art@uic.edu 901 S. Wolcott Ave, Rm E102 MSB
> Chicago, IL 60612-7341
Over the years we have had pretty much all the same problems as Art describes
with room temperature control.
A couple of additional comments. We have the electric reheat system in one of our
labs with four instruments and it still only seems to give about a 2 C range of
control.
One of our students had a problem where very good temperature stability was
required. She just ran the VT air through a coil of tubing in a large plastic
carboy of water. The water comes to equilibrium with the room, but filters out
the cycling of the A/C. We did not insulate any of the lines, but made the line
to the probe quite short. I don't remember the exact numbers, but the stability
was very good, less than 0.1 C as I recall.
To monitor the room temperature we have put a simple max/min thermometer
(available for about $30 from any of the scientific supply houses) in each lab.
It can be reset at the beginning of a critical experiment or just monitored from
time-to-time to catch any malfunctions of the A/C equipment.
Charlie
--Charles L. Mayne University of Utah Dept. of Chemistry 315 S. 1400 E. Rm Dock Salt Lake City, UT 84112-0850 Voice: (801)581-7413 FAX: (801)581-4763 or 8433 E-mail: mayne@chemistry.utah.edu http://www.chem.utah.edu/chemistry/facilities/nmr/nmr.html
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John A. Anderson wrote:
Over the years we have had pretty much all the same problems as Art describes with room temperature control.-------------------------------------------------------------------
John A. (Art) Anderson, Ph.D. http://www.rrc.uic.edu
Spectroscopist Spectroscopy Facility
voice: 312-996-6640 Research Resources Center (M/C 937)
fax: 312-996-0539 The University of Illinois at Chicago
email: art@uic.edu 901 S. Wolcott Ave, Rm E102 MSB
Chicago, IL 60612-7341A couple of additional comments. We have the electric reheat system in one of our labs with four instruments and it still only seems to give about a 2 C range of control.
One of our students had a problem where very good temperature stability was required. She just ran the VT air through a coil of tubing in a large plastic carboy of water. The water comes to equilibrium with the room, but filters out the cycling of the A/C. We did not insulate any of the lines, but made the line to the probe quite short. I don't remember the exact numbers, but the stability was very good, less than 0.1 C as I recall.
To monitor the room temperature we have put a simple max/min thermometer (available for about $30 from any of the scientific supply houses) in each lab. It can be reset at the beginning of a critical experiment or just monitored from time-to-time to catch any malfunctions of the A/C equipment.
Charlie
--
Charles L. Mayne University of Utah Dept. of Chemistry 315 S. 1400 E. Rm Dock Salt Lake City, UT 84112-0850 Voice: (801)581-7413 FAX: (801)581-4763 or 8433 E-mail: mayne@chemistry.utah.edu http://www.chem.utah.edu/chemistry/facilities/nmr/nmr.html--------------54B27282BDBB73F1F4394770--