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  • Author or Editor: J. Houtman x
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Abstract  

This article describes how research planning may lead to a situation where a basis is provided for the cooperation between a limited group of personel guided by a devotion towards the possibilities and on awareness of the limitations of the nuclear reactor for analytical purposes and research groups in various sciences such as chemistry, biology, medicine, agriculture, geology and archeology. Attention is paid to neutron activation analysis, the use of radioisotope tracers and to the specific requirements set for them by workers in the above mentioned fields.

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Abstract  

In recent years increased information is required about the distribution of elements at low concentration levels in the biosphere. Neutron activation analysis can play an important role if it can supply many data at relatively low cost. As some of the concentrations are too low for determination by non-destructive techniques, equipment for chemical separations on a routine basis is necessary. For environmental studies a separation scheme has been developed successfully for arsenic, antimony, cadmium, copper, mercury, selenium and zinc. It is based on a combination of distillation and ion-exchange. Special attention is paid to the prevention of interference from bromine and sodium. Additional information about chromium, cobalt, nickel and tungsten can easily be obtained. Experience gathered with an automated instrument for fifty samples a week is described.

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Abstract  

An automated post-irradiation chemical separation scheme for the analysis of 14 trace elements in biological materials is described. The procedure consists of a destruction with sulfuric acid and hydrogen peroxide, a distillation of the volatile elements with hydrobromic acid and chromatography of both distillate and residue over Dowex 2X8 anion exchanger columns. Accuracy, precision and sensitivity are tested with reference materials (BOWEN’s kale, NBS bovine liver, IAEA materials dried animal whole blood, wheat flour, dried potatoes, powdered milk, oyster homogenate) and on a sample of pooled human blood. Blank values due to trace elements in the quartz irradiation vials are also discussed.

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Abstract  

After 25 years of rapid development, neutron activation analysis is now in a period of maturing. In this period, the attention has to be focussed on improvement of sensitivity, precision and accuracy without an appreciate increase of analysis costs, and on decrease of the costs per analysis without affecting sensitivity, precision and accuracy. The present paper indicates how already well known technical and physical possibilities can be used to reach this aim.

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