Particle Loss Characterization #12 - 2013-03-06
Relative humidity (%):
- Ammonium sulfate
Particle measurement size range:
Particle generation method:
Atomized from dilute solution of ammonium sulfate through a Nafion drier and Polonium 210 neutralizer
Date of characterization experiment:
Months since calibration:
Wall loss experiment description:
Particles were introduced into the chamber at the desired concentration and left to decay at the studied environmental condition for several hours.
Wall loss rates calculation method:
The first-order rate coefficient (s-1) was calculated at each size bin by plotting the number concentration vs time trace of that size bin. Then the diameter vs. loss rate relationship was obtained and reported.
Frequency of particle loss experiments:
Wall loss correction description:
For a typical experiment, the time profile at each size bin is corrected for the loss rate at that size bin. There is an assumption that organic-coated aerosol behaves like ammonium sulfate. Generally, this correction technique is able to remove the loss trend of the aerosols during the experiment.
Link to supplemental information:
Crump, Flagan and Seinfeld, 1982: https://www.tandfonline.com/doi/pdf/10.1080/02786828308958636?needAccess=true
Characterization data file:
|ID||Name||Start date||Experiment Category||Reaction Type||Reactant(s)||Oxidant Name||Temperature||Humidity||Type of Seed||RO2 Main Fate||Data Sets (count)||Actions|
|94||2014 FIXCIT Study_20140106_Isoprene/Ozone/Water_Hydroxyl radical_No Seed_Isoprene + OH + O3, low NO, dry, no seeds||2014-01-06||Gas phase chemical reaction||Photooxidation||Isoprene, Ozone, Water||Hydroxyl radical||25||5||No Seed||HO2||11|
|95||2014 FIXCIT Study_20140113_ALPHA-PINENE/nitric oxide/OZONE/formaldehyde_Nitrate radical_Ammonium sulfate_HO2 fate, dry RH, seed added at end||2014-01-13||Gas phase chemical reaction||Dark oxidation||ALPHA-PINENE, nitric oxide, OZONE, formaldehyde||Nitrate radical||25||5||Ammonium sulfate||HO2||12|
|97||2014 FIXCIT Study_20140111_nitric oxide/ALPHA-PINENE/hydrogen peroxide_Hydroxyl radical_No Seed_Alpha-pinene + OH, high NO, dry, (NH4)2SO4 seed at end||2014-01-11||Gas phase chemical reaction||Photooxidation||nitric oxide, ALPHA-PINENE, hydrogen peroxide||Hydroxyl radical||26||5||NO||13|