UNASSIGNED: A versatile and compact sampling system, the Sequential Spot Sampler (S3) has been developed for pre-concentrated, time-resolved, dry collection of fine and ultrafine particles. Using a temperature-moderated laminar flow water condensation method, ambient particles as small as 6 nm are deposited within a dry, 1-mm diameter spot. Sequential samples are collected on a multiwell plate. Chemical analyses are laboratory-based, but automated. The sample preparation, extraction and chemical analysis steps are all handled through a commercially-available, needle-based autosampler coupled to a liquid chromatography system. This automation is enabled by the small deposition area of the collection. The entire sample is extracted into 50-100 l volume of solvent, providing quantifiable samples with small collected air volumes. A pair of S3 units was deployed in Stockton (CA) from November 2011 to February 2012. PM2.5 samples were collected every 12 hrs, and analyzed for @entity2555 ( @entity2556 ). In parallel, conventional filter samples were collected for 48 hrs and used to assess the new system's performance. An automated sample preparation and extraction was developed for samples collected using the S3. Collocated data from the two sequential spot samplers were highly correlated for all measured compounds, with a regression slope of 1.1 and r(2)=0.9 for all measured concentrations. S3/filter ratios for the mean concentration of each individual @entity2556 vary between 0.82 and 1.33, with the larger variability observed for the semivolatile components. Ratio for total @entity2556 concentrations was 1.08. Total @entity2556 concentrations showed similar temporal trend as ambient PM2.5 concentrations. Source apportionment analysis estimated a significant contribution of biomass burning to ambient @entity2556 concentrations during winter.

Time-resolved Characterization of Particle Associated XXXX using a newly-developed Sequential Spot Sampler with Automated Extraction and Analysis.

@entity2556 :: ('CHEBI:33848', 'Chemical') :: ['PAH', 'PAHs'] @entity2555 :: ('MESH:D011084', 'Chemical') :: ['polycyclic aromatic hydrocarbons']
@entity2555 :: (MESH:D011084,Chemical) :: ['Polycyclic Aromatic Hydrocarbons']
