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Kim,

A couple of (long-shot) suggestions:

1. have you independently checked the temperature of your furnace? and

2. what reactor packing are you using?  Are you 
using the WO3 & Cu packing, or the Cu-only 
packing?  A long time ago I used to use the WO3 & 
Cu packing, but it would sometimes give me SO2 
chromatography problems that drove me to 
distraction (IPA-distraction, not 
lolly-distraction, in my case).  Since switching 
to the Cu-only configuration, and adding V2O5 to 
each sample, I've generally had good SO2 
chromatography.

Good luck!

Cheers,
Simon


*****
Simon Poulson
Research Professor
Dept. of Geological Sciences & Engineering MS-172
University of Nevada - Reno
1664 N. Virginia St.
Reno, NV 89557-0138. USA
(775) 784-1104
Fax: (775) 784-1833
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*****



>Questions for NA1500 users.
>
>I am still battling my EA which is smearing my 
>sulfur peak over 200 seconds instead of the 
>usual 50.  I have tried all the usual things to 
>no avail.
>
>BUT I have now determined that I have a 
>compressed air leak where the line feeds into 
>the EA. The culprit is the little double block 
>of aluminium which the compressed air and oxygen 
>and He lines immediately feed into once entering 
>the EA.  The manual labels the blocks as a 
>'safety line' which consists of a single effect 
>microcylinder and two, 2 way single effect 
>microvalves.   The manual does not mention them 
>at all in the spares list. The air is coming out 
>of the little hole at the top of the block and 
>also where both the blocks join together, which 
>leads me to ask.
>
>
>1.	Is it normal for the aluminium blocks of 
>the safety line to leak compressed air at all 
>times?
>
>
>
>2.	Is this likely to cause enough of a 
>problem to prevent the bimatic valve operating 
>properly? Given that the compressed air gauge at 
>the front of the EA reads as it should and is 
>Teed in before the safety line.
>
>
>
>3.	I have measured the oxygen flow at the 
>oxygen vent at the front of the EA and it is 
>ALWAYS 25ml/min, even when doing an oxygen 
>injection.  Should the flow from the oxygen vent 
>slow down or stop when the bimatic valve is 
>actuated?
>
>
>
>4.	Could my poor peak be a result of the 
>oxygen regulator not working properly?  I notice 
>that the pressure gauge gives a dramatic jump 
>when the bimatic valve is closed although this 
>may have always happened. J
>
>
>
>There is also a small leak in the micro-solenoid 
>valve that powers the sample carousel but this 
>does not appear to cause any problems.
>
>
>If anyone has any insights they would be greatly 
>appreciated.  Because of this I have become a 
>highly valued customer at the lolly shop and I 
>don't think that that is good for my sugar 
>levels  J
>
>
>Regards
>Kim
>
>-----------------------------------------------------------
>Kim Baublys
>Stable Isotope Geochemistry Laboratory, Earth Sciences
>The University of Queensland, 4072
>Australia
>Ph   +61 7 3365 1131
>Fax +61 7 3365 1277
>http//www.uq.edu.au/geochem/
>