Laser microprobe mass spectrometry was applied to the identification of tropospheric aerosol particles on electron microscopic grids collected during aviation from Nagoya to the Wakasa Bay in the central part of Japan Island at the altitude of 14,500-5,000 ft. As the references, Na2SO4, (NH4)2SO4, NaNO3, NH4NO3 and NaCl particles prepared by a nebulizer were shot with a laser beam of several micrometers in diameter and the ions were analyzed mass spectrometrically. Soil samples were also analyzed to give aluminosilicate spectra. For atmospheric aerosol particles, characteristic species were identified as (NH4)2SO4 in most samples. Phosphate particles among samples taken at 14,500 ft in altitude were found. Soil particles were found below 9,500 ft. Chloride and soot were identified among the particles in 14,500 ft.
To estimate deposition of aerosol particles in a connecting part of a sampling line, the deposition fractions at pipe connections were experimentally investigated using abruptly expanding and abruptly contracting pipes with diameters between 0.68 and 2.5 cm. The results show that the deposition increases within 50 cm after change in the pipe diameter, and that the degree of increase is proportional to 1.5th ∼ 2nd power of Stokes number at both the expanding and the contracting pipes. However, the influence of deposition due to the sudden change in pipe diameter on the aerosol concentration will be small tor a long sampling line.