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Ouardi A.,Center National Of Lenergie Des Science Et Des Techniques Nucleaires | Askour A.,Hassan II University | Benchekroun D.,Hassan II University | Tamri H.,Oncology Center Al Kindy
2013 3rd International Conference on Advancements in Nuclear Instrumentation, Measurement Methods and Their Applications, ANIMMA 2013 | Year: 2013

Because it is absolutely inert in the human body, immune to attack from bodily fluids, compatible with bone growth, and strong and flexible, titanium is the most biocompatible of all metals. The purpose of this study was to investigate the dosimetric effect of various cerebral implant Titanium plate thickness (0.05-1.cm) irradiated by 4 MV photon beam using Monte Carlo (Fluka). The simulations result shows that increasing thicknesses of the Ti plate rise the dose deposition near to plate. Also the dose deposition is varying when the Ti plate is set in different depth from the surface of the water equivalent phantom (for example the dose deposition decrease about 8% for 1cm). The second part of this study is dedicate to investigate the effect of scattered radiation produced in a cerebral implant for various materials including Ti alloys such as Ti-6Al-7Nb, Ti-6Al-4V(α) and Ti-6Al-4V(β). © 2013 IEEE.

Ben-Bolie G.H.,University of Yaounde I | Ele Abiama P.,University of Yaounde I | Ele Abiama P.,Institute of Geological and Mining Research | Owono Ateba P.,University of Yaounde I | And 2 more authors.
Radiation Protection Dosimetry | Year: 2013

In order to estimate the soil-to-plant transfer factors (TFs) of some natural radionuclides, the activity of 238U and 232Th was measured in the soil and in agricultural crop samples collected from identified high background radiation areas in the southwestern region of Cameroon. The results showed that the 238U and 232Th TFs values were in the ranges 1.031022-12.231021 kg kg-1 and 5.031022-9.731021 kg kg-1, respectively. These computed TFs values were found to be globally higher than those proposed by the International Atomic Energy Agency. © The Author 2013. Published by Oxford University Press. All rights reserved.

Dercon G.,International Atomic Energy Agency | Mabit L.,International Atomic Energy Agency | Hancock G.,CSIRO | Nguyen M.L.,International Atomic Energy Agency | And 21 more authors.
Journal of Environmental Radioactivity | Year: 2012

This paper summarizes key findings and identifies the main lessons learnt from a 5-year (2002-2008) coordinated research project (CRP) on "Assessing the effectiveness of soil conservation measures for sustainable watershed management and crop production using fallout radionuclides" (D1.50.08), organized and funded by the International Atomic Energy Agency through the Joint FAO/IAEA Division of Nuclear Techniques in Food and Agriculture. The project brought together nineteen participants, from Australia, Austria, Brazil, Canada, Chile, China, Japan, Morocco, Pakistan, Poland, Romania, Russian Federation, Turkey, United Kingdom, United States of America and Vietnam, involved in the use of nuclear techniques and, more particularly, fallout radionuclides (FRN) to assess the relative impacts of different soil conservation measures on soil erosion and land productivity. The overall objective of the CRP was to develop improved land use and management strategies for sustainable watershed management through effective soil erosion control practices, by the use of 137Cs (half-life of 30.2 years), 210Pb ex (half-life of 22.3 years) and 7Be (half-life of 53.4 days) for measuring soil erosion over several spatial and temporal scales. The environmental conditions under which the different research teams applied the tools based on the use of fallout radionuclides varied considerably - a variety of climates, soils, topographies and land uses. Nevertheless, the achievements of the CRP, as reflected in this overview paper, demonstrate that fallout radionuclide-based techniques are powerful tools to assess soil erosion/deposition at several spatial and temporal scales in a wide range of environments, and offer potential to monitor soil quality. The success of the CRP has stimulated an interest in many IAEA Member States in the use of these methodologies to identify factors and practices that can enhance sustainable agriculture and minimize land degradation. © 2012 Elsevier Ltd.

Naji S.,Mohammed V University | Naji S.,Ibb University | Belhaj A.,Sultan Moulay Slimane University | Labrim H.,Center National Of Lenergie Des Science Et Des Techniques Nucleaires | And 5 more authors.
Physica A: Statistical Mechanics and its Applications | Year: 2014

Motivated by spintronic device applications, we engineer a superlattice model based on periodic tri-layers consisting of spins σ=12, S=1 and q=32 residing on the sites of a square lattice, interacting with an external magnetic field. We study its phase diagrams and magnetic properties. We determine the corresponding ground state phase diagrams. Then, we show that this Ising lattice model exhibits a ferromagnetic phase F1, two ferrimagnetic phases F2, F3 and an antiferromagnetic phase F4. It is found that the magnetic behaviors depend on the moduli space controlled by the exchange interaction couplings. More precisely, the hysteresis loops have been established. © 2013 Elsevier B.V. All rights reserved.

Belhaj A.,Universite Ibn Tofail | Belhaj A.,Center National Of Lenergie Des Science Et Des Techniques Nucleaires | Fahssi N.-E.,Universite Ibn Tofail | Saidi E.H.,Universite Ibn Tofail | Segui A.,University of Zaragoza
International Journal of Geometric Methods in Modern Physics | Year: 2011

We engineer U(1)n ChernSimons type theories describing fractional quantum Hall solitons (QHS) in 1 + 2 dimensions from M-theory compactified on eight-dimensional hyper-Kähler manifolds as target space of N = 4 sigma model. Based on M-theory/type IIA duality, the systems can be modeled by considering D6-branes wrapping intersecting Hirzebruch surfaces F0's arranged as ADE Dynkin Diagrams and interacting with higher-dimensional R-R gauge fields. In the case of finite Dynkin quivers, we recover well known values of the filling factor observed experimentally including Laughlin, Haldane and Jain series. © 2011 World Scientific Publishing Company.

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