AMMRL: back to the basics...another helium question

From: Rajan Paranji <paranji_at_chem.washington.edu>
Date: Thu, 12 Feb 2015 14:48:51 -0800

Dear All
         Hope it doesn't hurt to visit the basics and ascertain 'facts'
to remain so. During Helium fills, we are all familiar with seeing the
dripping droplets from the manifold. Over the years I have been fuzzily
convincing myself that this condensed O2 or N2. Today, I stuck a
thermocouple in a suitable spot in the manifold and connected the same
to a Fluke handheld temperature calibrator and found that the lowest
temperature reached was -153 degree C i.e. approx. 120 K.

    Liquid O2 boiling point is approx. 90.1 K and LN2 is 77 K. The drip
happens on the outer surface of the Helium manifold so evidently it is
condensing something from the atomosphere in the room. So, what is this
liquid ?

Thank you, as always, for indulging my naivete. Hope to see most of
you at the ENC in Asilomar !

Best Regards

Rajan
-- 
____________________________________
____________________________________
Rajan K Paranji, Ph.D.
NMR Facility Manager
Department of Chemistry
Room 65, Bagley Hall
University of Washington
Seattle, WA 98195
*ph: 206 685 2581
fax: 206 685 8665
email:paranji_at_chem.washington.edu  <mailto:paranji_at_chem.washington.edu>
____________________________________
Received on Fri Feb 13 2015 - 08:50:11 MST

This archive was generated by hypermail 2.4.0 : Mon Jun 19 2023 - 17:04:55 MST