PHYSICO-CHEMICAL DYNAMICS OF NANOPARTICLE FORMATION DURING LASER DECONTAMINATION AND CHARACTERIZATION

Acceleration of decommission and deactivation (D&D) activities of US Department of Energy (DOE) requires improved understandings of nanoparticle production and transformation during laser decontamination. Many material researchers have explored particle formation during laser energy-material interaction, but there are little data relevant to D&D work while laser energy is used to remove materials from contaminated surfaces. Fine particles are harmful to D&D workers and the environment. The focus of this research is to investigate the effects of the laser parameters and the chemistry of target samples on the dynamics and properties of produced particles. Data will facilitate better design of decontamination and deactivation strategies. There are three goals associated with achieving the required understanding of nanoparticle dynamics. (1) To develop baseline property data of laser-produced nanoparticles from samples of different bulk chemical composition and surface morphology. The data would include properties of particles such as the size from a few nanometers to a few micrometers, shape, distribution, and chemical composition. (2) To develop advanced particle instrumentation (for sizing and chemistry measurement) enabling higher resolution and shorter interval measurement, and (3) To develop computer simulation model to analyze and predict the dynamics of particles produced