This report describes the work done to further develop the infrared spectroscopic analytical method for the analysis of atmospheric aerosol particles, as well as some exploratory work on a new procedure for determining proton acidity in aerosol samples. Earlier work had led to the successful use of infrared (ir) spectrophotometry for the analysis of nitrate, ammonium, and neutral and acidic sulfates in aerosol samples collected by an impactor on a Mylar-film substrate. In this work, a filter-extraction method was developed to prepare filter-collected aerosol samples for ir analysis. A study was made comparing the ir analytical results on filter-collected samples with impactor-collected samples. Also, the infrared analytical technique was compared in field studies with light-scattering techniques for aerosol analysis. A highly sensitive instrument for aerosol analysis using attenuated total internal reflection (ATR) infrared spectroscopy was designed, built, and tested. This instrument provides a measurement sensitivity much greater (by a factor of 6 for SO4²⁻) than that obtainable using the KBr-pellet method. This instrument collects size- and time-resolved samples and is potentially capable of providing automated, near real-time aerosol analysis. Exploratory work on a novel approach to the determination of proton acidity in filter- or impactor-collected aerosol samples is also described. …

Report of activities of Argonne Chemical Engineering Division, including advanced battery project, electro-chemical project management, advanced fuel cell development, utilization of coal, magnetohydrodynamics heat and seed recovery technology, solar energy, fast reactor chemistry research, nuclear fuel cycle studies, magnetic fusion energy research, and basic energy science.

Given a mapping with a sparse Jacobian matrix, the problem of minimizing the number of function evaluations needed to estimate the Jacobian matrix by differences is investigated. This problem can be attacked as a graph coloring problem and this approach leads to very efficient algorithms. The behavior of these algorithms is studied and, in particular, it is proved that two of the algorithms are optimal for band graphs. Numerical evidence is presented which indicates that these two algorithms are nearly optimal on practical problems.