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We have recently decommissioned a VG Elemental PQ-I ICPMS purchased in 1987. "Bessie", as we affectionately referred to her, was a real workhorse that really did the job for us. We have some parts left over from her that might be of use to someone still running one of these models, or indeed later PQ models. We know from experience that it can be difficult to obtain these parts (some are no longer made or supported by the original manufacturer, as in the case of the Tracor MCA). These are: 2 X PQ-I Quad RF generator 2 X PQ-I lense supply 1 X PQ-I Tracor Northern MCA 1 X PQ-I Power controller 1 X PQ-I Quadrupole controller Contact us if you are interested in any of these Ray Ford Elemental Research Inc. North Vancouver, B.C. Tel: (604) 986-0445 Fax: (604) 986-0071 Email: eri@mindlink.bc.caReturn to Top
I need help!! how many helium molecules are there in one cubic centimeter at standard pressure (one atmosphere) at 72 deg F.?? Any help or reference would be appreciated! Thanks ! tmagi@onramp.netReturn to Top
CI Help
We have an HP5988 Mass Dectector (using an RTE-A data system) that is
used mostly for GC/MS in both EI and CI.
Recently we changed the multiplier and cleaned the entrance lens and
quadrapole unit. This markedly improved sensitivity as it should have.
However, sensitivity for small GC peaks does not work well in CI.
Although manual tuning indicates that the source is reasonably clean
(repeller and drawout have maxima), tuning drifts with time. The tune will
shift even during a 45 min run.
We are aware that response factors vary greatly with the composition
of the CI gas used. Using methane in the scan mode we can easily detect
the m+1 and m+29 ions of benzophenone at 1ug/ul MeOH level when 1ul of
solution is chromatographed with a DB5 capillary column with a 40/1 split.
We would appreciate any suggestions from anyone experienced with the
HP5988 and aware of the subtleties involved with CI. We would also
consider establishing a consulting arrangement with someone with no
conflict of interest with our business (likely someone from academia).
Irwin Ladd
OSi Specialties Group, A Witco Company
777 Old Saw Mill River Road
Tarrytown, New York 10591-6728
airlnc1@osispec.com
Return to TopUsed ZABE for sale, full working order 10,000amu resolution 8kV, EI/CI, FAB 11/73 datasystem For details please contact Annette Lovett at Micromass Canada Inc Tel 514 694 1200 Fax 514 694 6280Return to Top
Are any MS users interested in purchasing a used HP5971A MSD complete with HP5890 series II GC and HP7673 autosampler? The system is 6 years old and in excellent condition. We routinely can get 5 pg in the SIMS mode. I am interested in upgrading to the HP5973, so I would like to see of there is a market for the old one. Zora Djuric, Ph.D. Karmanos Cancer Institute Wayne State University 110 East Warren Detroit, MI 48201 (313)833-0715 ext.328 FAX (313)831-7518Return to Top
Dear Netters: We have from time to time problems with getting good results from our Bio-Ion 20 PDMS mass spektrometer. We use it more or less exclusively for peptide QC. Usually we dissolve the peptide in 30% acetonitrile and take 20 ul of it and add 4 ul 50% EtOH with 0.1% TFA. Mostly it works nicely but not allways. If it does not work we try more or less in tha dark different solvent and I do not really like this trial and error. Does anyone out there have a simple strategy how to find solvent that will give optimal PDMS data? yours BOSSE _______________________________________________________________________ ______ Bo Servenius, Ph.D | bo.servenius@bm.lu.se BM-unit | http://www.bm.lu.se Lund University | phone: +46-46-2220584 office P.O.Box 778 | +46-46-2224640 lab S-220 07 Lund | +46-46-159194 home Sweden | fax +46-46-2220568 Europe | pager: +46-0740-153870 ________________________________________|______________________________ ____Return to Top