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Dewar flask

Dewar flask [for Sir James Dewar], container after which the common thermos bottle is patterned. It consists of two flasks, one placed inside the other, with a vacuum between. The vacuum prevents the conduction of heat from one flask to the other. For greater efficiency the flasks are silvered to reflect heat. The substance to be kept hot or cold, e.g., liquid air, is contained in the inner flask. See low-temperature physics.

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"Dewar flask." The Columbia Encyclopedia, 6th ed.. . Encyclopedia.com. 28 Jun. 2017 <http://www.encyclopedia.com>.

"Dewar flask." The Columbia Encyclopedia, 6th ed.. . Encyclopedia.com. (June 28, 2017). http://www.encyclopedia.com/reference/encyclopedias-almanacs-transcripts-and-maps/dewar-flask

"Dewar flask." The Columbia Encyclopedia, 6th ed.. . Retrieved June 28, 2017 from Encyclopedia.com: http://www.encyclopedia.com/reference/encyclopedias-almanacs-transcripts-and-maps/dewar-flask

vacuum flask

vacuum flask Container for keeping things (usually liquids) hot or cold. A vacuum flask consists of double, silvered glass walls, separated by a near vacuum. This vessel is held in an insulated metal or plastic case. The vacuum reduces heat transfer by conduction of convection between the contents and the surroundings. The silvering on the glass minimizes heat transfer by radiation. James Dewar invented the vacuum flask in 1892.

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"vacuum flask." World Encyclopedia. . Encyclopedia.com. 28 Jun. 2017 <http://www.encyclopedia.com>.

"vacuum flask." World Encyclopedia. . Encyclopedia.com. (June 28, 2017). http://www.encyclopedia.com/environment/encyclopedias-almanacs-transcripts-and-maps/vacuum-flask

"vacuum flask." World Encyclopedia. . Retrieved June 28, 2017 from Encyclopedia.com: http://www.encyclopedia.com/environment/encyclopedias-almanacs-transcripts-and-maps/vacuum-flask