17-11-2009, 12:03 PM
cryogenics is the study of the production of very low temperature (below -150 °C, -238 °F or 123 K) and the behavior of mLiquefied gases, such as liquid nitrogen and liquid helium, are used in many cryogenic applications. Liquid nitrogen is the most commonly used element in cryogenics and is legally purchasable around the world. Liquid helium is also commonly used and allows for the lowest attainable temperatures to be reached.
These liquids are held in either special containers known as Dewar flasks, which are generally about six feet tall (1.8 m) and three feet (91.5 cm) in diameter, or giant tanks in larger commercial operations. Dewar flasks are named after their inventor, James Dewar, the man who first liquefied hydrogen. Museums typically display smaller vacuum flasks fitted in a protective casing
aterials at those temperatures.
for making cryogenics temperature normally linde hampson system is using
see more
http://en.wikipediawiki/Cryogenics
http://sdl.usu.edu/products-http://www-b...genics.pdf
http://physics.princeton.edu/mumu/target...020905.doc
http://scribddoc/22057879/Cryogenics-and-heat-treatment