Professor Kimberly Prather and research group University of California, San Diego

InstrumentMeasures Aerosol time-of-flight Individual particle size and composition mass spectrometers (4) Scanning mobility particle size (20 nm to 0.6 um) particle sizing systems (2) Ultrafine aerosol mass spectrometerThe composition of size selected particles down to 50 nm Aerodynamic particle sizing systems (3)Aerodynamic particle size (0.5 um to 10 um) Opticle particle counters (2)Opticle particle size (0.2 um to 10 um) NephelometersLight backscattering (visibility) Flow tubesUsed for measuring particle formation processes and heterogeneous chemistry on short time scales Smog chamber systemUsed for measuring particle formation, growth, and chemistry of particles under controlled conditions of relative humidity and UV flux Atmospheric Pressure Chemical IonizationExtremely sensitive technique for measuring Mass Spectrometer gas phase species concentrations Meteorological stations (3)Temperature, wind speed and direction, relative humidity NOx systemGas phase concentrations of NOx Ozone monitorGas phase concentrations of ozone SOx systemGas phase concentrations of SOx HPLC systemUsed for separation and detection of complex mixtures GC systemUsed for separation and detection of complex mixtures MOUDI impactorsSize segregated particle mass concentrations Tapered element oscillatingPM2.5 and PM10 mass concentration microbalance (TEOM) Nd:YAG laser systems (nanosecond) (6)Used for LDI at 266 nm (also 1064, 532, and 355 nm available) CO 2 laser systemUsed in 2-step LDI-TOFMS **Femtosecond IR laser (coming in Jan. 2002!!)Used for LDI in IR region In addition to the instruments above which are housed in our labs, we have access to a host of other analytical instruments including electron microscopy (particle shape), UV-Vis, Raman, and IR spectrometers, AtomicForce Imaging instruments, surface analysis instruments, and a wide range of mass spectrometers.

I.e., 1 COH unit: log(I 0 /I) 400 =0.01

PM = Particulate Matter -2

Benzo(a)pyrene * “Bay region” *

Nuclei mode Accumulation mode Coarse particle mode

Bailey, Clark, Ferris, Krause and Strong, “Chemistry of the Environment,” second edition (San Diego: Academic Press) 2002.