Particle Loss Characterization #35 - 2022-08-24


Dry ammonium sulfate

scanning mobility particle sizer (#510)

Kelvin's big bag of air

Temperature (°C):

Relative humidity (%):

Particle composition:

  • Ammonium sulfate

Particle measurement size range:
14 - 670 nm

Particle generation method:
Atomization of 0.06 M ammonium sulfate solution

Date of characterization experiment:

Months since calibration:

Wall loss experiment description:
H2O2 and O3 were injected concurrent with ammonium sulfate atomization to mimic the hydrocarbon oxidation experiments. After injections the chamber was mixed with pulses of air and allowed to sit undisturbed for 6.5 hours.

Wall loss rates calculation method:
The loss of each particle size was binned in Matlab and an exponential fit was performed to extract the first order loss in 1/minutes

Frequency of particle loss experiments:
As needed for particle type and RH

Wall loss correction description:
For SMPS data from SOA experiments, we select the particle loss file that most closely matches the particle type (pure organic, pure AS, mixed AS/org, or other) and then each size bin is corrected with the measured loss frequency. We check that the ~1 hour period that the particles equilibrate in the chamber prior to experiment start is corrected to zero loss (flat line) from the appropriate wall loss file.

Link to supplemental information:

Additional notes:

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