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aniline

(Encyclopedia)aniline ănˈəlĭn [key], C6H5NH2, colorless, oily, basic liquid organic compound; chemically, a primary aromatic amine whose molecule is formed by replacing one hydrogen atom of a benzene molecule w...

Ertl, Gerhard

(Encyclopedia)Ertl, Gerhard gĕrˈhärt ârˈtəl [key], 1936– German chemist, b. Stuttgart, grad. Univ. of Stuttgart (1961), Technical Univ., Munich (Ph.D 1965). After holding a number of lecturer and research p...

Prokhorov, Aleksandr Mikhailovich

(Encyclopedia)Prokhorov, Aleksandr Mikhailovich əlyĭksänˈdər mēkhīˈləvĭch prôˈkhərəf [key], 1916–2002, Russian physicist, b. Atherton, Queensland, Australia. In 1923 he was taken to the Soviet Union...

protonation

(Encyclopedia)protonation prōˈtənāˌshən [key], in chemistry, addition of a proton to an atom, molecule, or ion. The proton is the nucleus of the hydrogen atom; the positive hydrogen ion, H+, consists of a sin...

chemosynthesis

(Encyclopedia)chemosynthesis, process in which carbohydrates are manufactured from carbon dioxide and water using chemical nutrients as the energy source, rather than the sunlight used for energy in photosynthesis....

exobiology

(Encyclopedia)exobiology or astrobiology, search for extraterrestrial life within the solar system and throughout the universe. Philosophical speculation that there might be other worlds similar to ours dates back ...

alum

(Encyclopedia)alum ălˈəm [key], any one of a series of isomorphous double salts that are hydrated sulfates of a univalent cation (e.g., potassium, sodium, ammonium, cesium, or thallium) and a trivalent cation (e...

adsorption

(Encyclopedia)adsorption, adhesion of the molecules of liquids, gases, and dissolved substances to the surfaces of solids, as opposed to absorption, in which the molecules actually enter the absorbing medium (see a...

fainting

(Encyclopedia)fainting or syncope sĭngˈkəpē [key], temporary loss of consciousness caused by an insufficient supply of oxygen to the brain. It can be concurrent with any serious disease or condition, such as he...

fertilizer

(Encyclopedia)fertilizer, organic or inorganic material containing one or more of the nutrients—mainly nitrogen, phosphorus, and potassium, and other essential elements required for plant growth. Added to the soi...

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