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stellar structure

(Encyclopedia)stellar structure, physical properties of a star and the processes taking place within it. Except for that of the sun, astronomers must draw their conclusions regarding stellar structure on the basis ...

absolute zero

(Encyclopedia)absolute zero, the zero point of the ideal gas temperature scale, denoted by 0 degrees on the Kelvin and Rankine temperature scales, which is equivalent to −273.15℃ and −459.67℉. For most gase...

carbon dioxide

(Encyclopedia)carbon dioxide, chemical compound, CO2, a colorless, odorless, tasteless gas that is about one and one-half times as dense as air under ordinary conditions of temperature and pressure. It does not bur...

Frasch process

(Encyclopedia)Frasch process fräsh [key] [for Herman Frasch, the German-American chemist who devised it], process for the extraction of sulfur from subsurface deposits. Three pipes, one inside another, are sunk to...

solution

(Encyclopedia)CE5 Solubility curves solution, in chemistry, homogeneous mixture of two or more substances. The dissolving medium is called the solvent, and the dissolved material is called the solute. A solutio...

calendering

(Encyclopedia)calendering, a finishing process by which paper, plastics, rubber, or textiles are pressed into sheets and smoothed, glazed, polished, or given a moiré or embossed surface. The material is passed thr...

Bayer process

(Encyclopedia)Bayer process, procedure for obtaining alumina from the aluminum ore bauxite. The alumina can then be used for various industrial purposes or smelted to provide aluminum. The first step in the process...

liquefaction

(Encyclopedia)liquefaction, change of a substance from the solid or the gaseous state to the liquid state. Since the different states of matter correspond to different amounts of energy of the molecules making up t...

superconductivity

(Encyclopedia)superconductivity, abnormally high electrical conductivity of certain substances. The phenomenon was discovered in 1911 by Heike Kamerlingh Onnes, who found that the resistance of mercury dropped sudd...

compression

(Encyclopedia)compression, external stress applied to an object or substance, tending to cause a decrease in volume (see pressure). Gases can be compressed easily, solids and liquids to a very small degree if at al...