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plaster casting

(Encyclopedia)plaster casting, as a sculpture process, is of three kinds. One employs a waste mold, another a piece mold (both plaster of paris), and the third a gelatin mold; all reproduce the original clay or wax...

capillarity

(Encyclopedia)CE5 Capillarity: Water wets the walls of a capillary tube and thus rises, causing the upper surface, or meniscus, of the liquid to be concave; mercury does not wet the walls of a capillary tube and...

Horlivka

(Encyclopedia)Horlivka hôrˈləfkə [key], Rus. Gorlovka, city (1989 pop. 337,000), E Ukraine, in the Donets Basin. It is a major coal-mining and industrial center, with a major chemical complex. Founded in 1867, ...

precipitation, in chemistry

(Encyclopedia)precipitation, in chemistry, a process in which a solid is separated from a suspension, sol, or solution. In a suspension such as sand in water the solid spontaneously precipitates (settles out) on st...

piezoelectric effect

(Encyclopedia)piezoelectric effect pīēˌzōĭlĕkˈtrĭk [key], voltage produced between surfaces of a solid dielectric (nonconducting substance) when a mechanical stress is applied to it. A small current may be ...

colloid

(Encyclopedia)colloid kŏlˈoid [key] [Gr.,=gluelike], a mixture in which one substance is divided into minute particles (called colloidal particles) and dispersed throughout a second substance. The mixture is also...

states of matter

(Encyclopedia)states of matter, forms of matter differing in several properties because of differences in the motions and forces of the molecules (or atoms, ions, or elementary particles) of which they are composed...

amalgam

(Encyclopedia)amalgam əmălˈgəm [key], alloy containing mercury. The alloy may be liquid or solid, depending on the proportion of mercury, although all naturally occurring amalgams, i.e., those of gold and silve...

lanolin

(Encyclopedia)lanolin, greasy, yellow substance extracted from wool. When purified, it is used as a base for ointments and creams, as a lubricant, and in finishing and preserving leather. It is also a constituent o...

aerogel

(Encyclopedia)aerogel, any of a group of extremely light and porous solid materials; the lightest is less than four times as dense as dry air. Aerogels are produced from certain gels (see colloid) by heating the ge...