Radiation-detection tools

The last three chapters consider special aspects of radioanalytical chemistry that have become increasingly important and visible. Chapter 15 describes the automated systems that are used to measure radionuclides in the counting room and in the environment. Chapter 16 is devoted to identification and measurement of the radionuclides beyond the actinides. These are research projects at the cutting edge of radiochemistry that apply novel rapid separations in order to measure a few radioactive atoms before they decay. Much must be inferred from limited observations. In Chapter 17, several versions of mass spectrometers combined with sample preparation devices are described. The mass spectrometer, applied in the past as a research tool to detect a small number of radioactive atoms per sample, is now so improved that it serves as a reliable alternative to radiation detection for radionuclides with half-lives as short as a few thousand years. 

The radiation detection systems employed in radioanalytical chemistry laboratories have changed considerably over the past sixty years, with significant improvement realized since the early 1980s. Advancements in the areas of material science, electronics, and computer technology have contributed to the development of more sensitive, reliable, and user-friendly laboratory instruments. The four primary radiation measurement systems considered to be necessary for the modern radionuclide measurement laboratory are gas-flow proportional counters, liquid scintillation (LS) counters. Si alpha-particle spectrometer systems, and Ge gamma-ray spectrometer systems. These four systems are the tools used to identify and measure most forms of nuclear radiation. 

XANES) is known to be a sensitive technique to detect small changes in the chemical environment at low-Z elements. This capability is due to the use of the synchrotron radiation. This tool allows the sp and sp molecular hybridizations to be distinguished and therefore XANES is useful to identify the molecular structure of a chemical compound [10]. 

Radiation from a dirty bomb can emanate from a blast site in a contaminated plume of smoke or in contaminated debris. Radiation cannot be detected without special instruments, and radiation exposures can occur even without direct contact. Therefore, leaving a damaged building does not eliminate the risk of exposure. An effective tool to minimize or eliminate the potential for hazardous substance exposure is to move away from the site of the attack and into a building that provides protection from airborne contaminants. 

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