This technique is used to determine trace elements in a wide variety of materials, including rocks and other geological samples, ceramics, oils, plastics, metals, water, biological and botanical materials. The greatest use of CNAA has been in the area of short lived analyses. Delayed Neutron Counting Delayed Neutron counting is a sensitive, selective and rapid technique for determining uranium at ppm levels or lower. The McMaster DNC system is a fully automated, irradiation, analysis and data logging system, designed for efficient throughput. Prompt Gamma Activation Analysis Prompt gamma activation analysis looks at gammas emitted during neutron capture, instead of delayed gammas.
Valuable samples have special analysis requirements.
In this case, the nondestructive nature of PGAA can be fully exploited. Consequently, both residual activity and potential radiation damage to delicate samples is dramatically reduced. Dr. Denis Shaw, Professor Emeritus, and his team at McMaster mostly use MNR for PGAA, looking at various problems in the distribution of boron, gadolinium and samarium in terrestrial and lunar rocks in meteorites. The work done in this area has a common theme of understanding the principles governing the distribution of rare and dispersed elements in natural systems, as controlled by atomic and thermodynamic properties. The main diffraction instrument, which is in constant use, is the powder diffractometer supervised by Prof. J.E. Greedan of Chemistry.