Low Pressure Sieverts System
National Renewable Energy Laboratory
The National Renewable Energy Laboratory has developed a custom Sieverts system for highly accurate gas capacity measurements on small samples (10s of mg) sizes and lower pressures (<5000 Torr). Gas capacity isotherms can be collected at 77K or at any temperature between 0°C and 900°C. The system is extremely useful for mole-counting experiments where gases fixed to the sample (physi- or chemisorption) in vacuum and lower temperatures are released at higher temperatures and counted.