Non-metal fixed points
Research to develop new, non-mercury temperature reference cells using sulfur hexafluoride, carbon dioxide, and xenon to support international temperature standards below 273K.
This grant is no longer accepting proposals
NRC Research Associateship Programs has archived this opportunity.
Funder: NRC Research Associateship Programs
Due Dates: February 1, 2025 | May 1, 2025 | August 1, 2025 | November 1, 2025
Funding Amounts: $82,764 stipend plus $3,000 travel allowance; typical appointment duration 2 years.
Summary: Postdoctoral fellowship to develop new non-mercury temperature reference cells using sulfur hexafluoride, carbon dioxide, and xenon to support international temperature standards below 273 K.
Key Information: Open to U.S. citizens with a doctoral degree earned within the last 5 years; research conducted at NIST in Gaithersburg, MD; requires contacting a research adviser prior to application.
Description
This fellowship opportunity supports research at the National Institute of Standards and Technology (NIST) focused on developing new temperature reference cells that do not use elemental mercury. Due to regulatory restrictions on mercury and technological challenges with non-metal substitutes, there is a critical need for new temperature reference cells to support the International Temperature Scale (ITS) below 273 K.
The research targets two main areas:
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Drop-in replacement cells: Developing cells that substitute sulfur hexafluoride (SF6) or carbon dioxide (CO2) triple points for legacy mercury-based cells, focusing on the temperature range 200 K to 234 K. NIST has pioneered precise realization of the SF6 triple point using immersion-type cells and has preliminary research on CO2 cells. Other labs are advancing CO2 immersion cells as well.
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Xenon triple point cells: Developing new technologies to support xenon immersion-type cells at lower temperatures (161.406 K). Current xenon cells are small and incompatible with common immersion thermometric systems. NIST has patented designs combining compact Stirling coolers and multi-zone architecture to realize triple points of various elemental or molecular species between 70 K and 200 K using immersion cells.
Proposals leveraging advanced thermodynamic methodologies in physical chemistry and chemical engineering are encouraged.
