15th anniversary of the Central Institute for Isotope and Radiation Research of the Academy of Sciences of the GDR

The most important results of the activities of the Central Institute for Isotope and Radiation Research (ZfI) during 15 years since its foundation are reviewed: development of process analysis and technical diagnosis using radioisotopes at facilities of power industry, semiconductor industry, chemical industry and other industries; extension of radiometric analysis; ivestigation of the interactions between ionizing radiation and matter and the application of ionizing radiation in chemical industry, agriculture, forestry, food industry, electrochemical industry, and other industries; separation, application and analysis of stable isotopes in the exploration of native resources by isotope geochemical and radiogeochronological means including activation analysis and mass spectroscopy of trace elements; extension of the theory of isotope effects towards the theory of thermodynamic isotope effects in natural systems and its application in the exploration of the continental crust; and extension of 15N tracer techniques including partially automated emission spectrometric 15N analyzers and their application in the investigation of the nitrogen cycle in the soil - plant - animal - human system and in the exploration of the human nitrogen metabolism. (author)