We have been trying some low temp MAS using N2 boiloff to provide
clean dry N2 gas. Our N2 source is a standard 230 l high pressure (> 200 psi)
dewar with the "pressure building" valve. The problem is, even with the pressure
building valve fully open, we can't get enough flow for the bearing, drive, purge, and
VT requirements (pressure is fine). We just can't evaporate the N2 fast enough.
Has anyone out there found a solution to this problem? These are rented dewars, so we
can't really install in internal heater. Using compressed N2 cylinders is inconvenient
and a much more expensive source of N2. We have thought of maybe wrapping the
dewar in some sort of heating blanket to keep the pressure building system warm.
Thanks in advance,
-Kirk
Kirk Marat, Ph. D., NMR Facility Manager
Dept. of Chemistry
University of Manitoba
Winnipeg, MB, R3T 2N2, CANADA
ph. (204) 474-6259 FAX: (204) 474-7608
kirk_marat_at_umanitoba.ca
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Received on Tue Oct 26 2004 - 18:21:51 MST