Study of coincidence summing effect using Monte Carlo simulation to improve large samples measurement for environmental applications.

A new measurement model composed of High Purity Germanium detector HPGe including Lead Shield with a mixed source of Am-241, Cd-109, …in a soil matrix packed in a cylindrical container was developed by Monte Carlo N-Particles code MCNP5. The Monte Carlo models being largely used for efficiencies calculations in routine environmental radioactivity measurements of high volume soil samples. In order to validate the simulation, a multi-radionuclides soil matrix source in a cylindrical container is prepared.

Assessment of erosion: use of nuclear techniques and conventional methods-case of the Fergoug watershed, Algeria.

The importance of the soil degradation in the Mediterranean area, more particularly in Algeria, has revealed the need for a diagnosis of the erosion processes' dynamism. In this context, the present work discusses the results obtained by different approaches (conventional methods, Revised Universal Soil Loss Equation (RUSLE), and fallout radionuclides (use of FRNs)). The use of nuclear techniques (FRNs) such as Cesium-137, Lead-210, and Beryllium-7 as tracers can provide an invaluable amount of information on rates of soil loss that is associated with sheet and rill erosion as well as on the redistribution and transfer of that sediment within the landscape.

Monte Carlo calculations of the HPGe detector efficiency for radioactivity measurement of large volume environmental samples.

A fully detailed Monte Carlo geometrical model of a High Purity Germanium detector with a (152)Eu source, packed in Marinelli beaker, was developed for routine analysis of large volume environmental samples. Then, the model parameters, in particular, the dead layer thickness were adjusted thanks to a specific irradiation configuration together with a fine-tuning procedure. Thereafter, the calculated efficiencies were compared to the measured ones for standard samples containing (152)Eu source filled in both grass and resin matrices packed in Marinelli beaker.