The use of the 14N(d, p 0) 15N reaction for studies of nitrogen depth distribution in grains of barley and in samples of chromium steel

Abstract

The 14N(d, p 0) 15N reaction has been used to measure nitrogen depth distributions in single seeds of barley and in samples of chromium steel. In order to test the applicability of the method for plant breeding purposes we have studied 2000 grains of barley with the present technique. These grains are part of a larger material of about 50 000 grains grown and harvested under controlled biological conditions. The measured nitrogen distributions show striking correlations with parameters describing nitrogen level of fertilizer and time of harvesting. However, contributions in the spectra from silicon in the hull make the analysis somewhat complicated at the present stage. Six different samples of chromium steel were also studied. A beam of 3 MeV deuterons was used, and the distribution of nitrogen was studied to a depth of about 16 μm with a resolution of about 2 μm (fwhm). With an etching technique the nitrogen content could be measured further into the sample. In a layer a few μm thick at the surface the nitrogen concentration was found to be about a factor of two larger than in the restof the sample.