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( Refining)
Refining is the process of purification of a substance. The term is usually used of a natural resource that is almost in a usable form, but which is more useful in its pure form. For instance, most types of natural petroleum will burn straight from the ground, but it will burn poorly and quickly clog an engine with residues and byproducts. The term is broad, and may include more drastic transformations, such as the reduction of ore to metal (for which see Refining (metallurgy)). The refining of liquids is often accomplished by distillation or fractionation. Gases can be refined in this way as well, by being cooled and/or compressed until they liquefy. Gases and liquids can also be refined by extraction with a selective solvent that dissolves away either the substance of interest, or the unwanted impurities. Many solids can be refined by growing crystals in a solution of the impure material; the regular structure of the crystal tends to favor the desired material and exclude other kinds of particles. The use of silicon and other semiconductors in electronics is highly dependent on precise control of impurities, and a number of special techniques have been developed, such as zone refining.
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Refining Subcategories
Refining Articles
Acomplia: Refining Obesity by Jenifer D'souza
Obesity and over weight is a highly talked about modern disease and hence a lot of studies and researches have been done in order to find out the reasons and medicine of obesity. Obesity is dependant on the daily calorie intake of an individual and h...
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