US-Malaysia Cooperative Research: Elemental Analysis of Geological Materials by Glow Discharge Methods

本提案请求资助佛罗里达大学化学系Willard W. Harrison博士和马来亚大学化学系Tong Soo Loong博士进行为期24个月的合作研究，研究用辉光放电法分析地质材料的元素。他们将研究辉光放电作为原子化、激发和电离源，用于固体元素分析的质谱和原子发射。研究将集中在地质材料的检查，通过压实它们与各种基质。他们将研究样品的制备过程以及吸气剂作为基体和等离子体改性剂对清除反应性气体的影响。将对光谱干扰进行比较，并对不同的放电气体进行比较，以确定它们在辉光放电源中使用的任何最终优势。几种重要的分析技术可以有利地利用辉光放电的特性。固体样品可以直接处理，不需要样品溶解。一般来说，辉光放电是一种简单的双电极装置，在低压下充满稀有气体，通常是氩气。待分析的样品形成阴极。当电流通过该装置时，形成氩离子，冲击样品，并将原子溅射到等离子体中。碰撞过程随后激发和电离部分溅射的中性原子。然后可以用各种光谱技术来研究电离物质。在他们的研究中，合作者将解决使用辉光放电分析地质样品时遇到的几个问题。合作者是备受尊敬的科学家，他们过去的合作一直卓有成效。该项目与“发展中国家科学项目”的目标相关，该项目旨在通过科学信息、思想、技能和技术的交流以及在互利问题上的合作，提高美国科学家和工程师与发展中国家同行之间的合作水平。

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.