Proton induced .gamma.-ray analysis of atmospheric aerosols for carbon, nitrogen, and sulfur composition

Abstract

A technique for the simultaneous quantitative determination of carbon, nitrogen, and sulfur using in-beam y-ray spectrometry has been developed for use with atmospheric aerosol samples. Samples are collected on quartz filters, and the aerosol composltlon is determined by analyzing the y rays emitted following the inelastic scattering of 7.0-MeV protons.Samples are nondestructively irradiated for 1000 s in a helium atmosphere, are not subjected to reduced pressures, and can be used for subsequent analysis. Detection limits for atmospheric samples are in the pg/cm* range with a precision of 5 % . The technique is compared with several more conventional methods of analysis.

Elemental carbon concentrations: Estimation of an historical data base

“…Analysis of Light Elements (GRALE) technique (Macias et al, 1978 Both elemental carbon measurement methods are described by Delumyea et al (1980), and results of the reflectance analyses are reported by Conklin et al (1981). Analysis of the elemental carbon content of these filters using the laboratory reflectometer calibrated by Delumyea et al (1980) introduces a second optical instrument into this experiment in addition to Km samplers .…”

A Critical Review

“…Samples collected on quartz filters have been analyzed for carbon, nitrogen, and sulfur by determining the 7-rays emitted following the scattering of 7.0 MeV protons. 163 Elemental constituents for S, Cl, Br, K, Ca, Ti, Mn, Fe, Zn, and Pb have been determined for particles >0.25 nm aerodynamic diameter by sampling with cascade impactors and PIXE analysis. 164 This method has been used along with other analytical techniques to distinguish (NH 4 )2SO 4 from H2SO 4 by controlling relative humidity during particle sampling with cascade impactors.…”

Determination of low-z elements in atmospheric aerosols by charged-particle-induced nuclear reactions

“…This type of analysis is called an "absolute analysis." A common practice, however, is to use a 11 relative method 11 of analysis in which only the relative cross sections of a reaction at different incident particle energies are required.…”