An Optimized Method for Characterization and Verification of Nano Sized Uranium and Thorium Particles for Safeguards Purposes

Abstract

An optimized method that depends on preparation of nano-sized samples using ball mill technique (PM 400) and mounting it on cupper coated carbon grid was applied for microanalysis of particles to verify uranium and thorium existence. Five uranium and thorium bearing samples were analyzed by Scanning Electron Microscope (SEM) and Energy Dispersive X-ray (EDX) to verify the presence of uranium and thorium particles. High Resoluation Transmission Electron Microscope (HR-TEM) was used to image samples in order to verify the presence of different nano-sized particles. All samples were scanned by SEM at optimum conditions before and after applying the developed procedure; working distance =10 and 11 mm, voltage =30 kV, magnification value = X500, spot-size = 50, to screen the samples. The developed method is not time consuming and gives reliable results in case of heterogeneous samples and samples of low content of uranium and thorium.

Keywords: Scanning Electron Microscope (SEM), Nano particles, Safeguards, Uranium, Thorium.