Nitrogen, refrigerated liquid

SYNS NITROGEN, compressed (UN 1066) (DOT) NITROGEN, refrigerated liquid (ct ogenic liquid) (UN 1977) (DOT) NITROGEN GAS... 

Synonyms cas 7727-37-9 nitrogen, compressed nitrogen, refrigerated liquid nitrogen gas... 

Synonyms Nitrogen, compressed Nitrogen gas Nitrogen, refrigerated liquid... 

Nitrogen oxyfluoride. See Nitrosyl fluoride Nitrogen, refrigerated liquid. See Nitrogen Nitrogen trifluoride CAS 7783-54-2... 

Nitric Acid, other than red fuming 2031 44 Nitrogen, refrigerated liquid 1977 21... 

Fig. 1.11. Scheme of a sorption pump with liquid nitrogen refrigeration. 

A. Liquid Nitrogen and Liquid Air. Liquid nitrogen is the most commonly used refrigerant for the manipulation of condensable materials on a vacuum system because it is easy to use, inexpensive, and will not support combustion. Furthermore, its boiling point is low enough, — 196°C (77°K), to lower the vapor pressure of most materials below 10 3 torr, which is necessary for the quantitative transfer of condensible materials on the vacuum system. 

The high-Tc feature would permit the use of low-cost liquid nitrogen refrigerant, a savings on the order of twenty to one over liquid helium. 

The H2O is retained by the sintered disc, the other gases are transferred to another liquid nitrogen refrigerated trap through the open tap on the right. 

Constant-temperature baths or furnaces are needed to maintain the uniform temperature environment for comparison calibration. Stirred-liquid baths and temperature controllers have good characteristics as constant-temperature media due to their ability to maintain temperature uniformity [100]. The liquids used include refrigerants, water, oils, molten tin, and molten salt. Water can be used for temperatures between 0 and 100°C and oils above 300°C. Refrigeration units are available for commercial constant-temperature baths with alcohol as the working fluid and temperatures as low as -80°C. At NIST, special cryostats [8, 25] with liquid nitrogen or liquid helium as the coolant are used for comparison calibration at low tem-... 

LIQUID NITROGEN - Nitrogen in liquid form which is used as a low temperature refrigerant in expendable or chemical refrigerating systems. 

The 0.13% neon-helium bleed stream from the Kestner-type condenser is first concentrated by a condensation-rectification action, in heat exchange with liquid nitrogen. The liquid-nitrogen refrigerant used in this step is obtained from the supply of upper-column reflux liquid. An approximate composition of 46 % neon, 19 % helium, 2 % hydrogen,... 

Synonyms Dinitrogen monoxide Dinitrogen oxide Factitious air Hyponitrous acid anhydride Laughing gas Nitrogen monoxide Nitrogen oxide Nitrous oxide, compressed Nitrous oxide, refrigerated liquid... 

Fig, 4. Nitrogen refrigeration cycle with liquid oxygen pump. 

Fluorine is authorized for shipment in cylinders as a compressed gas under DOT and TC regulations, and as a liquefied low temperature gas in liquid nitrogen refrigerated tanks mounted on truck trailers by special permit of the DOT [5, 8]. 

TENSILE TESTS. Tensile tests at low temperatures were performed by immersing the specimen in a refrigerant liquid. A two-chamber test cell was constructed for testing at low temperatures. For tests at 78 K the inner chamber was filled with liquid nitrogen. For tests at 20 K, liquid hydrogen was used in the inner chamber with liquid nitrogen in the outer container. 

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