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powder

(Encyclopedia)powder, any mass of fine particles or dust prepared by various mechanical means, e.g., grinding of solid substances, or by chemical means, e.g., precipitation from solutions. In a special sense, the w...

Tokyo, University of

(Encyclopedia)Tokyo, University of, at Tokyo, Japan; founded in 1877. In the 1920s it became one of the first Imperial universities and remains one of the most prestigious in Japan. It offers degrees in letters, la...

von Klitzing, Klaus

(Encyclopedia)von Klitzing, Klaus, 1943–, German physicist, Ph.D. Univ. of Würzburg, 1972. He was a professor at the Technical Univ. of Munich (1980–85) and then director of the Max Planck Institute for Solid ...

bitumen

(Encyclopedia)bitumen bĭtyo͞oˈmən [key] a generic term referring to flammable, brown or black mixtures of tarlike hydrocarbons, derived naturally or by distillation from petroleum. It can be in the form of a vi...

septic tank

(Encyclopedia)septic tank, underground sedimentation tank in which sewage is retained for a short period while it is decomposed and purified by bacterial action. The organic matter in the sewage settles to the bott...

Brownian movement

(Encyclopedia)Brownian movement or motion, zigzag, irregular motion exhibited by minute particles of matter when suspended in a fluid. The effect has been observed in all types of colloidal suspensions (see colloid...

sintering

(Encyclopedia)sintering, process of forming objects from a metal powder by heating the powder at a temperature below its melting point. In the production of small metal objects it is often not practical to cast the...

crystal

(Encyclopedia)CE5 Types of crystal crystal, a solid body bounded by natural plane faces that are the external expression of a regular internal arrangement of constituent atoms, molecules, or ions. The formation...

specific gravity

(Encyclopedia)specific gravity, ratio of the weight of a given volume of a substance to the weight of an equal volume of some reference substance, or, equivalently, the ratio of the masses of equal volumes of the t...

iodoform

(Encyclopedia)iodoform īōˈdəfôrmˌ [key], CHI3, yellow crystalline solid that has a penetrating odor. It melts at 119℃ and is insoluble in water but soluble in ether or ethanol. Iodoform was formerly used as...