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heart-lung machine

(Encyclopedia)heart-lung machine, device that maintains the circulation of the blood and the oxygen content of the body when connected with the arteriovenous system; it is also called the pump oxygenator. The machi...

Wacker process

(Encyclopedia)Wacker process, an industrial process for the manufacture of ethanol by oxidizing ethene. For example, bubbling ethylene and oxygen when treated by an acidified water solution of palladium and cupric ...

Adelard of Bath

(Encyclopedia)Adelard of Bath ădˈəlärd [key], fl. 12th cent., English scholastic philosopher, celebrated for his study of Arabic learning. He translated Euclid from Arabic into Latin. His major works were Perdi...

complex ion

(Encyclopedia)complex ion, charged molecular aggregate (see ion), consisting of a metallic atom or ion to which is attached one or more electron-donating molecules. In some complex ions, such as sulfate, SO4−2, t...

chlorate

(Encyclopedia)chlorate pərklōrˈāt, –klôrˈ– [key], salts of chloric acid, HClO3, and perchloric acid, HClO4, respectively. Perchlorates are safer to handle than chlorates; they are more stable when expos...

Karst

(Encyclopedia)Karst kärst [key], Ital. Carso, Slovenian Kras, limestone plateau, W Slovenia, N of Istria and extending c.50 mi (80 km) SE from the lower Isonzo (Soča) valley between the Bay of Trieste and the Jul...

pyroxylin

(Encyclopedia)pyroxylin pīrŏkˈsĭlĭn [key], partially nitrated cellulose (see nitrocellulose). It is used in lacquers, plastics, and artificial leathers. Pyroxylin lacquers are made by dissolving pyroxylin in a...

hardening

(Encyclopedia)hardening, in metallurgy, treatment of metals to increase their resistance to penetration. A metal is harder when it has small grains, which result when the metal is cooled rapidly. Sometimes small ar...

hydrometer

(Encyclopedia)hydrometer hīdrŏmˈətər [key], device used to determine directly the specific gravity of a liquid. It usually consists of a thin glass tube closed at both ends, with one end enlarged into a bulb t...

nitric acid

(Encyclopedia)nitric acid, chemical compound, HNO3, colorless, highly corrosive, poisonous liquid that gives off choking red or yellow fumes in moist air. It is miscible with water in all proportions. It forms an a...