الفهرس 
Neutron fluxOnly 14 pages are availabe for public view
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Abstract
Activation analysis using thermal neutrons (NAB) makes possible the determination of a large number of elements with a high degree of sensitivity and accuracy in a variety of materials. During irradiation in a nuclear reactor of a sample to be analyzed, radioisotopes are formed from most of the elements present. When measuring the activated sample, the nature of the induced radioactivity yields qualitative inform tion on the composition of the sample. The activities of individual radionuclides are a measure of the concentrations of the related elements. So as to get a deeper insight in the fundamental principles of (n, ’1( ) activation analysis, e study Kas performed of the mathematical description of the (n, jlf ) reaction rate. Therefore it was necessary to consider the dependence of both the reactor neutron flux and the (n,~)ac tivation cross-section on the neutron energy. It was found most convenient to express the (n,’l( ) activation formula in the simple, but accurate HdGDAHL-convention, where reactor neutrons are classified in a subcadmium or epicadmiurn energy region, discriminated at the effective Cd-cut-off energy 0.55 eV.