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cyanide process

(Encyclopedia)cyanide process or cyanidation, method for extracting gold from its ore. The ore is first finely ground and may be concentrated by flotation; if it contains certain impurities, it may be roasted. It i...

Ketterle, Wolfgang

(Encyclopedia)Ketterle, Wolfgang, 1957–, German physicist, Ph.D. Max Planck Institute for Quantum Optics, Garching, Germany, 1986. He has been a professor at Massachusetts Institute of Technology since 1990. Kett...

bromide

(Encyclopedia)bromide, any of a group of compounds that contain bromine and a more electropositive element or radical. Bromides are formed by the reaction of bromine or a bromide with another substance; they are wi...

cellophane

(Encyclopedia)cellophane, thin, transparent sheet or tube of regenerated cellulose. Cellophane is used in packaging and as a membrane for dialysis. It is sometimes dyed and can be moisture-proofed by a thin coating...

lighting

(Encyclopedia)CE5 Incandescent lamp CE5 Basic fluorescent lamp lighting, light produced by artificial means to allow visibility in enclosures and at night. For stage lighting, see scene design and stage ligh...

isomorphism

(Encyclopedia)isomorphism īˌsəmôrˈfĭzəm [key], of minerals, similarity of crystal structure between two or more distinct substances. Sodium nitrate and calcium sulfate are isomorphous, as are the sulfates of...

benzaldehyde

(Encyclopedia)benzaldehyde bĕnˌzēnkärˈbənəl [key], C6H5CHO, colorless liquid aldehyde with a characteristic almond odor. It boils at 180℃, is soluble in ethanol, but is insoluble in water. It is formed by ...

tetraethyl lead

(Encyclopedia)tetraethyl lead tĕtˌrəĕthˈəl [key], (C2H5)4Pb, viscous, colorless, poisonous liquid. It is an organometallic compound prepared by reacting ethyl chloride with a sodium-lead alloy. When added to ...

tourmaline

(Encyclopedia)tourmaline to͝orˈməlĭn, –lēn [key], complex borosilicate mineral with varying amounts of aluminum, iron, magnesium, sodium, lithium, potassium, and sometimes other elements, used as a gem. It o...

urine

(Encyclopedia)urine, clear, amber-colored fluid formed by the kidneys that carries metabolic wastes out of the body (see urinary system). As the blood circulates it collects excretory products from the tissues and ...