Day 2 - Too much rain over paradise

Dakar was hit by a very heavy thunder storm last night, which resulted in widespread flooding. As a result of flooded roads, a couple of small landslides, several automobile accidents, some downed electrical equipment, and uncoordinated municipal traffic, it took nearly two hours to make it to the CERES lab today. The casualty count was at 6 last I was informed.

Though the background signal for both GC-ECD detectors had stabilized overnight (still high though ~ 1800), Kim Anderson (OSU) recommended using nitrogen gas from commercially available compressed gas tanks, rather than from the in house nitrogen generator. This was decided upon because 1) CERES currently can not assess the purity of N2 gas generated by their generator and 2) in order to keep OSU and CERES analytical methods as similar as possible. Anna and the CERES staff were informed of this and coupled one of the two nitrogen gas tanks to the GC-ECD. *Note that the purity of this nitrogen source has not been verified because it was not indicated on the tank. Anna contacted the vendor (Air Liquide, FR) and was informed that she would receive purity information via email. Anna and the CERES staff then hooked up the 2nd nitrogen tank (purity unknown for previously mentioned reasons) to the sample concentration manifold only to find that the tank was very low ~ 45-50 psi. She indicated that an additional tank would be ordered and present in the lab on Thursday.

Once the instrument detector readings stabilized post N2 source swap, I had Anna inject hexane instrument blanks in order to evaluate system chromatographic baseline. There were a few small peaks present on both the DB-17 and XLB columns, but none that warranted major concern. Interestingly, over the course of the analytical run the DB-17 baseline drifted from 1500 - 3500; I assume this is column bleed, but it caught me a bit off guard. The XLB did not show the same extent of baseline drift.

While hexane solvent blanks were running, Marie and Adama prepared a preliminary laboratory reagent blank in order to assess the cleanliness of CERES sample preparation apparatus. These samples were left to run overnight. I will report the results of this analysis on Thursday as the lab is closed tomorrow for religious purposes related to the Islamic tradition of Ramadan.

The care package, containing standards and other supplies shipped from OSU, has still not made it to CERES as of today.

Specific points:

1. Coupling the N2 tank to the GC-ECD took ~1 hour due to the tank's pressure regulator course adjustment knob falling off. The main hold up was locating an allen wrench. Additionally, installation of the regulator onto the second N2 tank took a similar amount of time for the exact same reason. It would benefit CERES  to house tools related to instrument maintenance in one tool box; this would minimize staff tool hunting time and facilitate more efficient laboratory workflow.
2.  Laboratory electrical power capacity was severely diminished today, perhaps related to last night's weather and today's flooding. We expereinced ~ 6 greyouts over the course of the day. Interestingly, chromatograms aquired during this time displayed baseline dips. CERES may benefit from a more robust power generator and a power signal stabilizer. 
3. Upon having Anna begin to analyze samples, I found the CERES currently does not organize analytical sequences or runs by a uniform procedure, but rather by operator specific conventions and cryptic names. This made it nearly impossible for me to locate files generated today. I suggested using a format similar to OSU and she agreed. It would benefit CERES to have an agreed upon analytical sequence/data file naming scheme amenable to multiple users and suited for laboratory traceability.