A new monitor for routine thermal and epithermal neutron fluence rate monitoring in k0 INAA

The Zr-Au set for monitoring the thermal and epithermal neutron fluence rate and the epithermal spectrum parameter alpha is not always practicable for routine application of INAA in well-thermalized facilities. An alternative set consisting of Cr, Au and Mo provides values for the thermal neutron fluence rate, f and alpha that are not significantly different from those found via the Zr-Au method and the Cd-covered Zr-method. The IRMM standard SMELS-II was analyzed using the (Au-Cr-Mo) monitor and a good agreement was obtained.

Inorganic chemical composition of native trees of the Atlantic Forest

The Atlantic Forest with its exuberant vegetation of high level of biodiversity is classified as one hotspot of the world. Chemical composition of leaves from native trees and underlying soils was evaluated by INAA. The predominant species Euterpe edulis, Bathysa meridionalis, Hyeronima alchorneoides, Marlierea tomentosa, Gomidesia flagellaris, and Gomidesia spectabilis belonging to the diverse plant families were studied. Euterpe edulis, the most abundant understory specie, presented the lowest element concentrations except for Zn. Some variation in chemical composition was noted, however, the chemical specificity of tree species can be more predominant than the soil variability for the obtained leaf concentrations. Factor values obtained through the Monte-Carlo assisted factor analysis were used for species discrimination, The results indicate that chemical investigation of native trees is a quite promising tool for biodiversity studies in the Atlantic Forest.

Nuclear and conventional methods for soil determination in sugar cane industry. Validity of sampling procedure

Scandium and ash methods' performances were compared in terms of soil content assessment in sugar cane loads, emphasizing the common sampling drawbacks. Both methods are adequate for such determination in controlled conditions. The scandium has demonstrated better analytical characteristics, since it is free from interferences of cane matrix, which decreases the accuracy of the ash method in normal mill conditions.

Evaluation of the washing system efficiency in sugar cane mills by neutron activation analysis

The effectiveness of industrial washing operation in minimizing soil in sugar cane delivered to mills is evaluated. Instrumental neutron activation analysis was the nuclear analytical technique chosen for this work, with Fe, Hf, Sc, and Th selected as soil tracers. On the basis of differences between elemental concentration of integral and prepared cane, that is before and after washing, the feasibility of the method for evaluation of the washing efficiency is demonstrated.