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Сосуд для хранения горячих или холодных веществ, например, жидкого воздуха.

It consists of two flasks, one inside the other, separated by a vacuum. The vacuum greatly reduces the transfer of heat, preventing a temperature change. The walls are usually made of glass because it is a poor conductor of heat; its surfaces are usually lined with a reflective metal to reduce the transfer of heat by radiation. Dewar used silver. The whole fragile flask rests on a shock-absorbing spring within a metal or plastic container, and the air between the flask and the container provides further insulation. The common thermos bottle is an adaptation of the Dewar flask. Dewar invented the Dewar flask in 1892 to aid him in his work with liquid gases. The vacuum flask was not manufactured for commercial/home use until 1904, when  two German glass blowers formed Thermos GmbH. They held a contest to rename the vacuum flask and a resident of Munich submitted "Thermos", which came from the Greek word "Therme" meaning "hot." In 1907, Thermos GmbH sold the Thermos trademark rights to three independent companies: The American Thermos Bottle Company of Brooklyn, NY; Thermos Limited of Tottenham, England; and Canadian Thermos Bottle Co. Ltd. of Montreal, Canada.

Категории: Физика
Dewar, James
1842 — 1923
Sir James Dewar, (1842-1923) was a chemist and physicist, best known for his work with low-temperature phenomena. Dewar was born in Kincardine, Scotland, and educated at the University of Edinburgh. He was professor of experimental natural philosophy at the University of Cambridge, England, in 1875 and professor of chemistry at the Royal Institution of Great Britain in 1877, where he was appointed director of the Davy-Faraday Research Laboratory. Dewar developed structural formulas for benzene (1867). He studied the specific heat of hydrogen and was the first person to produce hydrogen in liquid form (1898) and to solidify it (1899).  He constructed a machine for producing liquid oxygen in quantity (1891). He invented the Dewar flask or thermos (1892) and co-invented cordite (1889), a smokeless gunpowder, with Sir Frederick Abel. His discovery (1905) that cooled charcoal can be used to help create high vacuums later proved useful in atomic physics. Dewar was knighted in 1904. (Thermos is a proprietary name or trademark applied to a type of Dewar flask protected by a metal casing.) (http://inventors.about.com/library/inventors/blthermos.htm?once=true& ) Джеймс Дьюар - английский физик и химик, член Лондонского королевского общества (1877).Окончил Эдинбургский университет (1861). Профессор Кембриджского университета (с 1875) и Лондонского королевского института (с 1877). Президент Химического общества Англии (1897).Дьюар исследовал карбонильные соединения, озон. В 1871 предложил структурные формулы бензола и пиридина.Основные работы Дьюара относятся к изучению тепловых явлений. В 1872 разработал методы измерения теплоёмкости при низких температурах и обнаружил её уменьшение при понижении температуры.В 1898 впервые получил жидкий водород и определил его константы.Изобрёл особый сосуд (сосуд Дьюара), в котором тела могут длительное время сохранять свою температуру.Исследовал изменение электропроводности металлов в зависимости от температуры.Совместно с П. Кюри экспериментально доказал (1904), что при радиоактивном распаде радона образуется гелий.(http://www.alhimik.ru/great/dewar.html )