Hi all
Brian is correct in that there is an inherent problem with the OI Model 1030 which replaced the 1010.  Brian is the first to have been installed last fall with a 1030 (Aurora) and these problems began to show up.  A second system was installed in Canada just before Xmass and the hope was that OI fixed the problems and we could retrofit all other instruments for IRMS use.  Well, it did not work. A hardware and software patch was quickly done by OI in January and I returned to the Canadian site for a second time to finish the upgrade.  It was a fiasco again.
 
Finally the unit was returned to OI and the company admitted that they had not fully understood the needs for IRMS use and assumed it would work.  This is now on their priority to fix.  They also caught another problem that was not expected with the IR detector.  Here is what they have done since:
 
- The unit did not really like working with helium.  The flow controller and fritz were all wrong.  This has been fixed and is working in the factory to keep continuous flow.
- The IR detector is different from the 1010.  The 1010 had a nitrogen-air gas front window that protected the IR from helium.  The new one was under vacuum.  As I mentionned in my 2003 article, glass (quartz in particular) is porous to helium and destroys detectors and emittor( e.g. X-ray tubes).  The IR would last about 2 weeks under helium flow.  The new IR replacement goes back to the 1010 style and will be retrofitted to all IRMS application and will work in standalone as well.  Our IR is still working 7 years later on the 1010 with constant helium flow.
- The gas save mode was not really saving anything and I asked if they would make it fully work (as a bonus).  It seems that this is now in the system.
 
The canadian agent, Graham Hughes, has been very good at helping us to get these issues resolved.  OI will be installing and testing the Canadian unit within the next few weeks and then all further units will be upgraded for IRMS work.  Oi is in direct communication with myself to resolve all issues to make this a turnkey system and I believe they are going to acheive it shortly, if not already done in the test lab.  The features of the 1030 are supperior to the 1010 and once fully working will be the one to have.  We are also working on replacing our aging 1010 within the next 12 months with the Aurora.  I guess we have to look at this as short term pain for long term gain.
 
In the article due out in L&O:Methods by Chris Osburn (US Naval Research) and myself we show that with good reagent blank control you can analyse down to 2-3ml of seawater at <1ppmC.  Chris even recently tested 1ml of seawater with surprisingly good reproducibily on DOC.  The key for seawater DOC analysis is the persulphate concentration and blank reduction where we show the way to acheive this with the IRMs and the chemistry.  The nature of the design of the Aurora should help make this a routine analysis in a relatively short time.
 
Gilles
 
Gilles St-Jean
Chercheur / Research Scientist
Université d'Ottawa / University of Ottawa
Sciences de la Terre / Earth Sciences
140 Louis Pasteur, Ottawa, Ontario, Canada K1N 6N5
Tel: 1-613-562-5800 xt 6830 (Bureau / Office)
                    xt 6839 (Bureau / Office Lab)
                    xt 6836 (IRMS lab)
Téléc. / Fax: 1-613-562-5192
Courriel / E-mail: [log in to unmask]
Toile / Web: www.isotope.uottawa.ca




________________________________

De: Stable Isotope Geochemistry de la part de Brian Jones
Date: jeu. 2007-03-29 02:15
À: [log in to unmask]
Objet : Re: [ISOGEOCHEM] Does the TOC-IRMS work well?



Hi Marilyn and others,
We have the Aurora 1030W interfaced with our Delta V plus. This system has
great potential, however, at this point in time the Aurora (at least the
unit we have) has some significant issues that need attention. These include
problems regulating sample temperature and what appears to be valve
configuration mistakes in the firmware. These problems effect its
reliability as a stand alone instrument without considering the IRMS
interfacing. The valve problem is easily fixed, I think, but I have
encountered little assistance from OI in a resolution so far. Another item
that could use some work is start signal timing between the two instruments.
At present it is less than desirable and requires long Isodat run times
which must include dead time where the Aurora is doing its thing. Other
difficulties that you may face is with saltwater. A significant amount of Cl
gas is liberated in the reaction with persulfate. I understand Gilles
expects a paper out soon to address this issue, but I have already found a
way to deal with this in our analyses.
At present we only use the Aurora with the IRMS for DIC13, which it does
very well (0.1per mill SD). The valve problems exist in the DOC reaction
step and results in loss of sample CO2 before detection takes place, thus
these numbers are not reliable.
In my opinion, the 1010 is currently the best option for the interface.
However, once the issues on the Aurora are fixed it too could be a good
investment, but my advice would be to wait until these have been fixed and
save yourself the frustration.

Cheers,

Brian Jones
Senior IRMS Research Technician
Coastal Biogeochemistry Centre
School of Env. Sci & Mngmt
Southern Cross University
Lismore, NSW, Australia, 2480
Lab 02 6626 9565
Cell 04 3225 9046

----- Original Message -----
From: "Anthony Aufdenkampe" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Thursday, March 29, 2007 2:58 PM
Subject: Re: [ISOGEOCHEM] Does the TOC-IRMS work well?


> Marilyn and others,
>
> Here is what I have as a TOC-IRMS system.  As you probably correctly
> assumed, I've interfaced an OI-Analytical Model 1010 TOC analyzer
> (http://www.oico.com/default.aspx?id=refurbequip) to a DeltaPlus XP using
> the method of Gilles St. Jean (2005, RCMS 17: 419-428).  In 2005, we
> purchased an interface (combustion/reduction column, GC column and
> perchlorate trap) from Gilles and had him come set it up for us, so we are
> starting out with hardware identical to what Gilles used for his paper.
> Since then we've made some minor modifications to the method (sparge and
> peak timing on the OI-1010, etc.) and to the hardware (gas switching to
> reduce standby costs, etc.).
>
> The bottom line is that the instrument works very well and has potential
> to
> work even better.  A single sample or standard analyzed 8-10 times in a
> row
> gives a precision of <0.1 per mil, and real field duplicate samples
> typically show a deviation of <0.2 per mil.  At present, we're running a
> 10
> mL sample, and therefore can get good data down to 2 mgC/L (=20 ug C =
> about
> 1 V for mass 44) and reasonable data after blank correction down to 0.75
> to
> 1.0 mgC/L.  The standard deviation (after blank correction) of a standard
> curve that spans a range of 0.6 to 5 mgC/L is generally 0.2 to 0.6 per
> mil.
> Our blanks appear to be equivalent to ~1 ug C.  In summary, the data
> quality
> is equivalent to what is typical of real world EA-IRMS output.
>
> I'm expecting that data will improve as we continue to tweak the system.
> We
> are starting to oxidize 20 mL (the instrument max), to improve our data
> for
> low TOC samples.  Also, because the OI-1010 comes with a spaghetti tangle
> of
> 1/8" and 1/16" Teflon tubing for transporting liquids and gases, we're in
> the process of converting all of this to low permeability Halar tubing,
> and
> hope to see a big improvement in our blank (we've noticed a high Ar
> baseline
> and Ar pulses when certain valves switch in the OI-1010).  Better yet for
> all of you, the OI-1030
> (http://www.oico.com/default.aspx?id=product&productID=95) has now
> replaced
> the 1010, which is no longer made.  We did a demo of the 1030, and it is
> much better made than the 1010, with much simpler plumbing (less Teflon &
> likely more reliable), two reaction chambers for nearly double the
> throughput, and much better software.  We'll be upgrading as soon as we
> get
> the $$.
>
> So, although I enjoy being one of the few kids on the block with this toy,
> I
> would recommend without reservation this system to others.
>
> Cheers,
> Anthony
>
> _____________________________________________________________________
> Anthony K. Aufdenkampe, Ph.D.
> Assistant Research Scientist - Isotope & Organic Geochemistry
> Stroud Water Research Center
> 970 Spencer Road
> Avondale, PA 19311
> Tel:  610-268-2153 ext. 263
> Fax   610-268-0490
> http://www.stroudcenter.org/about/aufdenkampe.htm
>
>
> -----Original Message-----
> From: Stable Isotope Geochemistry [mailto:[log in to unmask]] On
> Behalf
> Of Marilyn Fogel
> Sent: Wednesday, March 28, 2007 11:23 AM
> To: [log in to unmask]
> Subject: [ISOGEOCHEM] Does the TOC-IRMS work well?
>
> Any insight on this, Anthony? Any other faithful readers trying this
> method
> out?
>
> Should we buy? Should we wait for you to do all the hard work?
>
> Marilyn
>