Cryogenic Cylinders

Matrix isolation as a GC detector was commercialized in the mid-1980s. The GC effluent is mixed normally with argon (ca. 2 %) and then trapped on a rotating gold-coated cryogenic cylinder at about 12K. The eluted molecules are isolated from each other in an argon matrix, which forms a solid track on the surface. Reflection-absorption spectra are collected from the surface after the trapping. 

Cryogenic cylinder An insulated metal cylinder contained within an outer protective metal jacket. The area between the cylinder and thejacket is normally under vacuum. The cylinders range in size from a Dewier (similar to a small thermos) up to 24 in in diameter and 5 ft in length. Examples of materials found in these types of cylinders are argon, helium, nitrogen, and oxygen. 

Low-boiling-point materials can cause frostbite on contact with living tissue. While this is an obvious hazard with cryogenics, e.g. liquid nitrogen or oxygen, cylinders of other liquefied gases also become extremely cold and covered in frost as the contents are discharged. 

Nickel Alloys Alloy C-4 (16 Cr, 16 Mo, Balance Ni) and alloy C-276 (16 Cr, 16 Mo, 3.5 W, 5 Fe, balance Ni) have been used for closure seals on cryogenic gas cylinders because the alloys retain all their ductility down to -327°C (—557°F). The impact strength at liquid nitrogen temperatures is the same as that at room temperature. 

Traditionally, inerts have been obtained from sources such as high-pressure gas cylinders or tube trailers or through evaporation of cryogenic liquids from bulk tanks. Other sources of inerts include (NFPA 69, Standard on Explosion Prevention Systems, National Fire Protection Association, 2002 FM Global, Loss Prevention Data Sheet 7-59, Inerting and Purging of Tanks, Process Vessels, and Equipment, 2000)... 

Standard on Fire Protection for Laboratories Using Chemicals Recommended Practice on Materials, Equipment and Systems Used in Oxygen-Enriched Atmospheres Standard for the Storage, Use, and Handling of Compressed Gases and Cryogenic Fluids in Portable and Stationary Containers, Cylinders, and Tanks Liquefied Petroleum Gas Code... 

Cryogenic materials Established data on properties of weld and base metals in LHj. Hydrogen diesel engine Tested a 100 kW single cylinder engine. 

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