الفهرس 
Chapter (1) Literature SurveyOnly 14 pages are availabe for public view
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Abstract
In this study, a modified cold grid cathode penning ion source is constructed and characterized; to obtain a high current of nitrogen ions. The effect of four samarium cobalt permanent magnet rods on the output ion beam current is
studied using argon gas. The output ion beam current at different pressures and grid cathode diameters are measured using nitrogen gas. It is found that at the optimum grid cathode diameter equal to 14mm, pressure equal to 9 x 10–4mbar, and discharge current equal to 1.8 mA, a maximum output ion beam current is equal to 220 μA using nitrogen gas.
Also, the output ion beam current is measured at different pressures and optimum grid cathode diameter using argon and hydrogen gases. The effect of applied negative extraction voltages on the extracted ion beam current at the optimum parameters is determined using argon, hydrogen, and nitrogen gases. It is found that the value of the ion beam is twice its value without extraction voltage.
The spinel ferrite nanoparticles with composition PbxCd(1-x)Fe2O4; X=(0,0.2,0.4,0.6)are successfully synthesized using hydrothermal process. The structural, surface morphology and magnetic properties are characterized using XRD, FTIR, EDX analysis, TEM micrograph, SEM techniques, and VSM, respectively.
Ferrite samples are irradiated with low-energy nitrogen ion beam. The structural, surface morphology and magnetic properties for samples are characterized by using XRD, TEM micrograph, SEM techniques, and VSM, respectively after ion beam irradiation.
Mass attenuation coefficient for the synthesized NPs materials is calculated theoretically by using Micro Shield v5 (5.03-00056) software.
The mass attenuation coefficient and the halve value thicknesses for synthesized samples are measured experimentally by 60Co and 137Cs gamma sources before and after ion beam irradiation. A good agreement between theoretical calculations and experimental investigations is found before ion beam irradiation. A good enhancement in material shielding characteristics was found after ion beam irradiation.
The neutron macroscopic cross section for the samples is studied before and after ion irradiation. It is obtained that, an enhancement in ΣT slow neutrons absorption cross section depend on the decrease in the crystal size for the irradiated samples.