METHOD AND APPARATUS FOR MEASURING WEAK IONIC ACTIVITIES OF A SAMPLE STREAM IN AN AUTOMATIC ANALYSIS APPARATUS

摘要

A sample stream is conditioned by the addition of reagents and the ion concentration is measured by means of a measuring system which can be connected to an arrangement for releasing an appropriate calibrating substance. The calibrating substance used is a soluble glass for the defined release of a known quantity of the ions to be measured, and the reference concentration is established directly in the sample stream. There is therefore no need for a calibrating solution or a metering pump for the latter, and disturbances due to the undesired transfer of impurities and reactive ions are avoided. The method is particularly suitable for the analysis of Na+, the soluble glass being a sodium polyphosphate glass.