Master of Science
Direct solid sampling is an area of analytical research that has generated a large amount of interest in recent years. Two analysis systems offering fast and nondestructive methods of determining the elemental composition of substances, without requiring complicated sample preparation procedures, are laser ablation inductively coupled plasma mass spectroscopy (LA-ICPMS) and radio frequency glow discharge mass spectroscopy (rf-GDMS). A Cetac LSX-200 laser system coupled to a LECO Renaissance ICPMS was utilized to analyze coal and ash samples prepared by incorporation into a lithium borate matrix to form a disk. In addition, a VG 9000 Glow Discharge Mass Spectrometer (GDMS) with Nier-Johnson reverse ion optic geometry, equipped with a radio frequency source (rf-source), was used for the determination of nonconductors or insulators in addition to the normal metals and semiconductors previously determined by dc-source analysis. Further addition of a pulse generator to the rf-source resulted in a variable duty cycle, allowing greater ionization efficiency without the risk of catastrophic damage to the sample. The results of this research indicate that the LA-ICPMS system can be used to directly determine the composition of ash samples, with further method development, and that the Prf-GDMS system can be used successfully to analyze nonconductive solid samples including bone tissue.
Miller, Joseph, "Direct Multielemental Analysis of Solid Samples Using Laser Ablation Inductively Coupled Plasma Mass Spectometry and Pulsed Radio Frequency Glow Discharge Mass Spectrometry" (2003). Masters Theses & Specialist Projects. Paper 556.