Instrument - Scanning Mobility Particle Sizer
Scanning Mobility Particle Sizer
What is being measured:
Particle size distribution
Data recording software:
Data analysis software:
Raw data time resolution:
Analysis data averaging:
Sensitivity to temperature (and correction method, if applicable):
Sensitivity to relative humidity (and correction method, if applicable):
Sample preparation method:
Sample residence time (chamber to instrument) (seconds):
Length of tubing (cm):
Instrument flow rate:
Tubing inner diameter:
Chemical identification method:
Data analysis method:
Counts at each size bin as determined by CPC is corrected for particle charging efficiency, diffusional losses of particles in the DMA, the DMA transfer function and diffusional broadening of the DMA transfer function, and the counting efficiency the CPC and inverted to produce size distributions, surface area concentrations and volume concentration.
Calibration occurs through addition of a known amount of seed, and subsequent comparison to pre-weighed filter samples collected at a flow rate of 14 LPM over a period of 30 minutes. Corrections can be applied to the observed volume concentration based on the mass collected.
Calibration drift estimate:
Low (on the order of weeks)
Uncertainty estimation method:
Uncertainty of particle mass concentration is on the order of 30% based on comparison to filter collection. Uncertainty arises from corrections for particle charging efficiency, diffusional losses of particles in the DMA, the DMA transfer function, diffusional broadening of the DMA transfer function, and counting efficiency of the CPC used to convert the measure particle mobility distribution to particle volume concentration.
Link to supplemental information:
To convert from volume concentration to mass concentration, multiply by a known density, as determined in the publication the data is from, an estimation based on bulk composition (Kuwata, 2012, EST, 787-794), or from an assumed density, in order of descending presence.
(i - lx) dN/dlogDp (Dp) (+/- 10%); (lxi) Number concentration (+/- 20%) (lxii) Surface Area concentration (+/- 30%) (lxiv) Volume Concentration (+/- 30%)
(i - lx) cm-3 nm-1; (lxi) cm-3; (lxii) um2 cm-3; (lxiii) um3 cm-3