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Campaign news...

Some updates concerning the campaign...

- Finally, we have received the ok that the BTEX is with the transport company in France and will leave for HCMC within the next couple of days. The last piece of equipment finally starting its journey to Vietnam. Cross your fingers that it will get through customs without problems!

- We have measured the LPG gas sold here in Vietnam with the calibrated GC in order to quantify the contents of other VOC which might contaminate our measurements. The main components of LPG are propane, iso-butane, n-butane. Another substance which cannot be identified is present in non-neglectable quantity, probably a butylene or propylene. Other substances are well below 3 ppb in a propane concentration level of 800 ppb, thus less than 1%. Thus, we can probably use LPG for our tracer experiments.

- The instruments in the truck (CO, SO2, NO/NOx, O3, PM2.5) are in a deplorable condition. Pumps are all strongly corroded and have not been serviced for decades, CO does not stabilize and values vary incredibly, O3 lamp has to be replaced, SO2 is fine after major overhaul, NO/NOx is probably ok after pump revision. The calibration unit was broken (and nevertheless used for calibration by Victory Co.) and is now working fine again. The O3 generator inside remains to be tested with a calibrated NO/NOx unit or the O3 unit. The pressure fluctutations at the exit of the zero air generator is not buffered with an expansion volume and thus the MFCs cannot compensate for the rapid pressure fluctuations. The industrial PC in the truck which is supposed to record the data, crashed every 5 mins and reboots. In brief, many things still remain to be done.

- Tomorrow we'll move the truck to the street and start measuring background of propane/butane with the GC. The goal is to start liberating tracer on next weekend. Instruments for classical pollutants will remain broken or uncalibrated for the moment. A technician of Victory Co. will probably fly in from Hanoi within the next couple of days to have a look.

- And then some pictures to make this blog entry more colorful...
Upper left: Getting the MGC101 power supply +/-15V channel repaired.
Upper right: Strange mesurement wheel of the CO11M where half is missing.
Bottom: Excursion 10km outside of HCMC to use calibration gas.
Posted by Oliver Fuhrer on Monday 8 January 2007 at 16:31