Three items:
UPDATE ON MY R2D2 MAGNET:
I am happy to report my r2d2 magnet that was giving me problems is now
holding LN2 for a week as it used to. Thanks to everyone who offered
to help me out with the vacuum adapter, particularly Eric Enwall of the
U. of OK @ Norman who lent me one of his. Pumping down to 3.1E-7 did
the trick (the ice bridge must have eventually boiled off of the warm
region of the can and condensed evenly on the cold surface). Sometimes
I don't know what I'd do without the AMMRL...
REQUEST FOR INFORMATION FROM THOSE WHO PURCHASED NMR INSTRUMENTATION 5-8
YEARS AGO:
Please give me feedback on what you think the vendors did well and not
so well. In particular, I would like information on: reliability,
cost-of-parts, repair turnaround time, phone/e-mail technical support
quality & timeliness.
REQUEST FOR INFORMATION FROM THOSE WHO RECENTLY BOUGHT NEW CONSOLES OR
SYSTEMS:
I'm currently attempting to negotiate the purchase of some 500 MHz NMR
instrumentation and would like to hear from people who have recently done
the demo thang on how their demos went, the various perceived strengths
and weaknesses of the vendors, the pluses and minuses of trying to include
specialized items (probes, shim sets). In particular, any comments
relating to the following will be greatly appreciated:
sensitivity, rf stability
shim set quality, esp. re: temp gradients in bore and heat dissipation
ability to meeting specs
giving and meeting delivery and installation dates
quality and timeliness of warranty service work
phone/e-mail technical and applications support
quality of newest version of software
earlier software compatibility
automated gradient shimming
automated diagnostics
automated calibration
HRMAS/nanoprobe comparison (oops, I was doing so well to keep it non-vendor
specific!)
I've read the stuff on computer platforms, and I have a very keen sense of
the purchase price (can you say 4-5 iterations?) and about how far the
vendors are willing to go.
If I get sufficient responses I will post. AS THIS SUBJECT IS A TOUCHY
ONE, I WILL ASSUME THAT ALL COMMENTS ARE MADE IN CONFIDENCE AND CAN BE
ONLY POSTED WITHOUT NAMES OR OTHER IDENTIFYING INFORMATION. IF ANYONE
WANTS TO RESPOND AND WISHES TO HAVE THEIR COMMENTS WITHHELD, PLEASE SAY
SO.
Jeff
Dr. Jeffrey H. Simpson jsimpson@mit.edu
Instrumentation Facility Director 617/253-1812 office
Department of Chemistry, 18-0090 617/253-1806 lab
Massachusetts Institute of Technology 617/253-0873 fax
77 Massachusetts Avenue, Cambridge, MA 02139-4307 USA