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A particle induced γ-ray emission methodology employing the O(p,p′γ)O ( E = 1982 keV) nuclear reaction is described for the non-destructive determination of bulk oxygen in materials. The development of the methodology follows a comprehensive measurement of the thick target yields of the 1982 keV prompt γ-rays in the 3.0-4.2 MeV proton energy region and a systematic assessment of such analytical features as the limit of detection, probing depth, precision and accuracy. The methodology is validated by analyzing binary, ternary and multinary oxides. It is simple and rapid, and in combination with prompt γ-ray producing reactions involving the other constituents, enables the complete compositional analysis of oxygen bearing materials. [ABSTRACT FROM AUTHOR]

The 10 B/ 11 B isotopic ratio and the atomic composition of boron carbide, an important non-metallic ceramic, have been determined non-destructively by the particle induced γ-ray emission (PIGE) and elastic backscattering spectrometry (EBS) techniques with proton beams. The analysis has been performed on powder as well as sintered ceramics containing boron in natural or 10 B enriched composition. The PIGE technique, performed at a 4.0–4.2 MeV proton energy, utilizes the 10 B(p,αγ) 7 Be, 10 B(p,p′γ) 10 B and 11 B(p, p′γ) 11 B nuclear reactions for (a) the isotopic analysis of boron and (b) the determination of total boron, and the 13 C(p,p′γ) 13 C nuclear reaction for the determination of carbon. The irradiation conditions were optimized by determining the thick targets yields of prompt γ-rays, characteristic of these reactions, in the 3.0–4.2 MeV proton energy range. The quantitative analysis was performed by comparison with standards taking into account the attenuation of γ-rays in the specimens. The uncertainty in the determination of the 10 B/ 11 B isotopic ratio and the B/C atomic ratio is about 2% and about 5% respectively. The analysis by EBS, on the other hand, involves the 10 B(p,p) 10 B, 11 B(p,p) 11 B and 12 C(p,p) 12 C elastic scatterings at the 2.0 MeV proton energy. This method too yields satisfactory results. Between the two, PIGE is the method of choice for bulk analysis while EBS is useful in discerning compositional variations in surface regions. [ABSTRACT FROM AUTHOR]