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A cryopump or a "cryogenic pump" is a vacuum pump that traps gases and vapours by condensing them on a cold surface, but are only effective on some gases. The effectiveness depends on the freezing and boiling points of the gas relative to the cryopump's temperature.
The pulse tube refrigerator (PTR) or pulse tube cryocooler is a developing technology that emerged largely in the early 1980s with a series of other innovations in the broader field of thermoacoustics.
Nitrogen is a liquid under −195.8 °C (77.3 K).. In physics, cryogenics is the production and behaviour of materials at very low temperatures.. The 13th International Institute of Refrigeration's (IIR) International Congress of Refrigeration (held in Washington DC in 1971) endorsed a universal definition of "cryogenics" and "cryogenic" by accepting a threshold of 120 K (−153 °C) to ...
The working fluid is 3 He, which is circulated by vacuum pumps at room temperature. The 3 He enters the cryostat at a pressure of a few hundred millibar . In the classic dilution refrigerator (known as a wet dilution refrigerator ), the 3 He is precooled and purified by liquid nitrogen at 77 K and a 4 He bath at 4.2 K.
At least six major areas of cryobiology can be identified: 1) study of cold-adaptation of microorganisms, plants (cold hardiness), and animals, both invertebrates and vertebrates (including hibernation), 2) cryopreservation of cells, tissues, gametes, and embryos of animal and human origin for (medical) purposes of long-term storage by cooling to temperatures below the freezing point of water.
The sorption pump is a cyclic pump and its cycle has 3 phases: sorption, desorption and regeneration. In the sorption phase the pump is actually used to create a vacuum. . This is achieved by cooling the pump body to low temperatures, typically by immersing it in a Dewar flask filled with liquid nitro
Evolutionary biology, in particular the understanding of how organisms evolve through natural selection, is an area of science with many practical applications. [1] [2] Creationists often claim that the theory of evolution lacks any practical applications; however, this claim has been refuted by scientists.
A noble diode pump is a type of ion pump used in high-vacuum applications that employs both a chemically reactive cathode, such as titanium, and an additional cathode composed of tantalum. The tantalum cathode serves as a high-inertia crystal lattice structure for the reflection and burial of neutrals, increasing pumping effectiveness of inert ...