Analysing coloured smoke | PearlTM or QuestTM?

^{The Royal Air Force Aerobatic Team or ‘Red Arrows’, commonly use an oil that does not include harmful chlorinated solvents along with a specifically prepared liquid dye.}

 ^{Diesel is injected into the hot exhaust from the jet engine. This reaches over 400 degrees centigrade. The mixture vaporises immediately upon release and the colours are produced by mixing dye with the white vapour.}

 ^{Safety measures}

^{Testing these dyes and oils ahead of performance is crucial, firstly to ensure that the pilot isn’t at risk of accident from combustible contaminants in the dye or diesel.}

 ^{The safety of those watching at 1500ft or more below can rely on ensuring dangerous levels of chemicals aren’t present in the mixture.}

^{The PearlTM liquid analysis accessory is great for testing oils, as we’ve discussed in the Specac application note PearlTM: New and Used Motor and Hydraulic Oils. But what about liquid dyes?}

 ^{We also know that the QuestTM ATR accessory is a very suitable accessory for the ATR spectroscopic analysis of paints along with other liquid and solid samples. But the PearlTM is unique for testing liquids in that it aids transmission IR spectroscopic analysis, not ATR.}

 ^{In one application note we compared our QuestTM and PearlTM in the testing of greases. Overall it became apparent that if you were only interested in testing liquid samples, the PearlTM offered the greater spectral resolution, even for samples which weakly absorb in the IR.}

^{Figure 1 shows an IR spectrum taken from 3500 – 600 cm-1 of Castrol LM grease using both accessories. The resolution of the PearlTM is about 10 times stronger than that of the QuestTM and so shows the absorption strength of the sample to a much more detailed degree.}

 ^{The QuestTM is still a very reliable accessory, but one which has a greater appeal because it can test any sample of any consistency, with great accuracy and minimal sample preparation time.}

 ^{If you’re flying off any time soon to perform some aerial acrobatics, make sure your smoke is safe (and the right colour) with the Specac PearlTM liquid IR transmission analysis accessory!}