High-Flux Irradiation of Open Samples

The irradiation of large samples of biological material in a high neutron flux enables the extention of trace element analysis into the ng to pg range, but raises several problems as gamma heating and radiolysis degrade the samples. Gamma heating increases the pressure to a point where either a very large irradiation container is necessary or a container which can endure the high pressure. Several methods to overcome these problems have been published. The irradiation of open samples was performed as an alternative to these methods. Temperature effects on biological material during irradiation in a high and in a low neutron flux were compared. As an example, wheat was irradiated in open containers allowing simultaneous temperature measurement in the sample during irradiation.