Word: vacuums
(lookup in dictionary)
(lookup stats)
Dates: during 1940-1949
Sort By: most recent first
(reverse)
...applications of high vacuum are making industrial history...
...promising is the use of high vacuum in magnesium production that WPB officials call the development one of the outstanding technical achievements of the war. Several big magnesium plants, including Henry Ford's River Rouge, have already adopted it. And the major penicillin makers are now using high-vacuum dehydration...
Empty Heads. The new methods were parented by a four-year-old Boston research firm headed by a lanky, sharp-chinned, young M.I.T. graduate, Richard Morse. His researchers call themselves "specialists in nothing." They were not the first to work in their rarefied field, for high-vacuum apparatus is an old tool in the laboratory and in small-scale manufacturing. But Morse's National Research Corp. developed machinery which for the first time makes it possible to use a high vacuum in large-scale mass production...
...basis of a vacuum's industrial usefulness is that it makes it easier to change a solid or liquid into a gas. Under normal atmospheric pressure (760 mm.), the pressure of air molecules prevents or retards the evaporation of molecules from liquids or solids. Evaporation may be speeded by 1) heating, which makes molecules move faster (as in boiling water), or 2) reducing air pressure. Heating, however, may change the chemical make-up of a substance (e.g., heated food often loses vitamins, heated magnesium oxidizes). Industrially, the ideal method would be to evaporate a substance while it is frozen...
Larger Pumps. That is exactly what Morse's group did, by reducing air pressure to a rarity hitherto unattainable on an industrial scale. To do this, they had to maintain a high vacuum of less than 1 mm. air pressure inside the huge tanks and pipes where materials were to be treated. Mechanical pumps (which work not by sucking but by sweeping air out of a vessel) are not very effective at pressures below...