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vulcanization

(Encyclopedia)vulcanization vŭlˌkənəzāˈshən [key], treatment of rubber to give it certain qualities, e.g., strength, elasticity, and resistance to solvents, and to render it impervious to moderate heat and c...

photochemistry

(Encyclopedia)photochemistry, study of chemical processes that are accompanied by or catalyzed by the emission or absorption of visible light or ultraviolet radiation. A molecule in its ground (unexcited) state can...

nonlinear dynamics

(Encyclopedia)nonlinear dynamics, study of systems governed by equations in which a small change in one variable can induce a large systematic change; the discipline is more popularly known as chaos (see chaos theo...

mutation

(Encyclopedia)mutation, in biology, a sudden, random change in a gene, or unit of hereditary material, that can alter an inheritable characteristic. Most mutations are not beneficial, since any change in the delica...

gravitation

(Encyclopedia)gravitation, the attractive force existing between any two particles of matter. The term gravitygravity is commonly used synonymously with gravitation, but in correct usage a definite distinction is...

generator

(Encyclopedia)CE5 Generator: The rotation of the conducting coil of wire in a magnetic field causes a current to be induced in the coil. This current is alternating and is conducted from the coil by means of sli...

germanium

(Encyclopedia)germanium jərmāˈnēəm [key] [from Germany], semimetallic chemical element; symbol Ge; at. no. 32; at. wt. 72.63; m.p. 937.4℃; b.p. 2,830℃; sp. gr. 5.323 at 25℃; valence +2 or +4. Pure german...

Geiger counter

(Encyclopedia)Geiger counter or Geiger-Müller (G-M) counter gīˈgər-mŭlˈər, –myo͞oˈlər [key], instrument for the detection and quantitative determination of ionizing radiation such as the alpha and beta ...

frost

(Encyclopedia)frost or hoarfrost, ice formed by the condensation of atmospheric water vapor on a surface when the temperature of the surface is below 32℉ (0℃). In the formation of frost, a gas (water vapor) is ...

Fukushima

(Encyclopedia)Fukushima fo͝oko͞oˈshĭmä [key], city, capital of Fukushima prefecture, N Honshu, Japan, on the Kiso ...