What do Dewar containers do?

Dewar containers are designed to keep substances, especially liquefied gases like liquefied nitrogen or oxygen, at low temperatures by minimizing heat transfer. They achieve this through a vacuum insulation between two walls that prevents heat from entering or escaping the container. This feature makes them ideal for storing cold materials over extended periods while preventing them from warming up.

While Dewar containers primarily serve the purpose of keeping things cold, options such as storing radioactive materials, containing pressurized gases, or protecting against chemical spills are functions related to different types of containers or equipment and are not the primary function of Dewar containers. Their design and function target cryogenic applications specifically.