Weighing System (IMAGE) Physikalisch-Technische Bundesanstalt (PTB) Caption This is a weighing system to determine the mass flows of ethanol and water. Credit PTB Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.