[en] As a basis for future heavy element experiments off-line tracer studies with rhenium have been carried out to model the chemical behavior of nielsbohrium (element 107) in thermochromatographic separations with oxygen as a reactive gas. A specific version of the On-Line Gas Phase Separation Apparatus, OLGA, has been developed to perform on-line chemical separations of short-lived products from heavy ion nuclear reactions, and to enable α-spectroscopic measurements of the separated products after condensation on thin foils. (orig.)