This proposal requests funds to permit Dr. Willard W. Harrison, Department of Chemistry, University of Florida, and Dr. Tong Soo Loong, Department of Chemistry, University of Malaya, to pursue, for a period of 24 months, cooperative research on the elemental analysis of geological materials by glow discharge methods. They will study the glow discharge as an atomization, excitation, and ionization source for the elemental analysis of solids by mass spectroscopy and atomic emission. The research will center on the examination of geological materials by compacting them with a variety of host matrices. They will study sample preparation procedures and the effect of getter agents as matrix and plasma modifiers to scavenge reactive gases. Comparisons will be made of spectral interferences, and alternative discharge gases will be compared to determine any resultant advantages to their use in glow discharge sources. Several important analytical techniques can advantageously utilize the characteristics of a glow discharge. Solid samples can be handled directly without the need for sample dissolution. The glow discharge, in general, is a simple two-electrode device, filled with a rare gas, usually argon, at low pressure. The sample to be analyzed forms the cathode. When an electric current is passed through the device, argon ions are formed, impact upon the sample, and sputter atoms into the plasma. Collision processes subsequently excite and ionize fractions of the sputtered neutral atoms. The ionized matter may then be studied by various spectrometric techniques. In their research, the collaborators will address several problems encountered in using the glow discharge to analyze geological samples. The collaborators are highly respected scientists whose past association has been productive. This project is relevant to the objectives of the Science in Developing Countries Program which seeks to increase the level of cooperation between U.S. scientists and engineers and their counterparts in developing countries through the exchange of scientific information, ideas, skills, and techniques and through collaboration on problems of mutual benefit.
