The State of Liquid Helium near Absolute Zero.

1939 ◽  
Vol 43 (1) ◽  
pp. 49-69 ◽  
Author(s):  
F. London
Keyword(s):  
Liquid Helium ◽  
The State ◽  
Absolute Zero

scholarly journals CRYOGENIC AIR CONDITIONING OF MOTOR VEHICLES

2014 ◽  
pp. 100-103
Author(s):  
M. JAIVIGNESH ◽  
DR. B. VIJAYA RAMNATH
Keyword(s):  
Low Temperature ◽  
Liquid Helium ◽  
Liquid Nitrogen ◽  
Low Temperatures ◽  
Air Conditioning ◽  
Absolute Zero ◽  
Motor Vehicles ◽  
Air Conditioning System ◽  
Low Temperature Refrigeration ◽  
Physical Phenomena

Cryogenics is the branch of physics and engineering that involves the study of very low temperatures (below 123 K), how to produce them, and how materials behave at those temperatures. It is frequently applied to low temperature refrigeration applications such as in the study of physical phenomena of materials at temperature approaching absolute zero and in the liquefaction of gases. Liquefied gases such as liquid nitrogen and liquid helium are used in many cryogenic applications. Using liquid nitrogen as a refrigerant reduces chloro-fluorocarbon (CFC) emission in atmosphere and it is an eco-friendly technique. This paper deals with usage of liquid nitrogen in air conditioning of motor vehicles. First the preparation of liquid nitrogen is discussed, followed by its storage and working as a refrigerant in air conditioning system. This is followed by its advantages and draw backs.

scholarly journals XIII. The variation of molecular surface-energy with temperature

1893 ◽  
Vol 184 ◽  
pp. 647-673 ◽  
Keyword(s):  
Surface Tension ◽  
Critical Temperature ◽  
Surface Energy ◽  
Absolute Temperature ◽  
The State ◽  
Absolute Zero ◽  
Molecular Surface ◽  
Molecular Weights ◽  
Similar Formula ◽  
Volume Energy

1. The well-known relation of volume-energy to temperature, expressed by the equation pv = RT, and the simple relations between p, v, and T when the substance examined is in the state of gas, together with the constancy in the value of R, if the weights of unit volumes of gases taken are proportional to their molecular weights, have led us to make experiments on the surface-tension of liquids in the hope of discovering relations as direct and simple We were guided to this research by experiments by Eötvös, which shall, be discussed later.* We have not been disappointed; it appears that a similar formula expresses with moderate accuracy the variation of surface-energy with temperature; it may be stated in similar terms, using the symbols γ for surface-tension, i. e., the force exerted along a linear centimetre of the liquid ; s for a surface over which are distributed a number of molecules the same for all liquids; k for a constant analogous to R in the gaseous equation; and τ for temperature measured in Centigrade degrees downwards, the critical temperature being taken at zero. An equation completely analogous to the gaseous equation, pv = RT, should therefore be γ s = kt . That this is reasonable follows from the following consideration :—In the gas equation, pv = RT, if v be kept constant, p decreases with fall of T, until where p = 0, T = — 273°, or absolute zero; the origin of the scale of absolute temperature is also the origin of the scale of pressure.

scholarly journals Atomic Theory of Liquid Helium Near Absolute Zero

1953 ◽  
Vol 91 (6) ◽  
pp. 1301-1308 ◽  
Author(s):  
R. P. Feynman
Keyword(s):  
Liquid Helium ◽  
Absolute Zero ◽  
Atomic Theory

Blood Freezing to Nearly Absolute Zero Temperature: −272.29°C

1981 ◽  
Vol 103 (1) ◽  
pp. 24-26 ◽  
Author(s):  
E. G. Cravalho ◽  
C. E. Huggins ◽  
K. R. Diller ◽  
W. W. Watson
Keyword(s):  
Liquid Helium ◽  
High Vacuum ◽  
Human Erythrocytes ◽  
Absolute Zero ◽  
Zero Temperature ◽  
Normal Range ◽  
Biological Assays ◽  
Intracellular Potassium ◽  
Edta Solution ◽  
2,3 Dpg

Human erythrocytes were collected in ACD anticoagulant, glycerolized with an equal volume of 8.6 M glycerol, 8 percent glucose, 1 percent fructose, and 0.3 percent Na2 EDTA solution, sealed in glass ampules, and frozen to −272.29°C (0.86°K) in liquid helium under high vacuum. Biological assays performed after thawing and three-stage dialysis to remove the glycerol showed less than 1 percent hemolysis. Intracellular potassium, 2,3 DPG, and ATP were within the normal range.

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