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transistor

(Encyclopedia)CE5 Simple transistor circuit transistor, three-terminal, solid-state electronic device used for amplification and switching. It is the solid-state analog to the triode electron tube; the transist...

vault

(Encyclopedia)CE5 Vaults vault, ceiling over a room, formed in any one of a variety of curved shapes. The architects of the Renaissance and baroque periods abandoned Gothic methods and returned to Roman vault...

polyp and medusa

(Encyclopedia)CE5 Polyp and medusa stages in the life cycle of Obelia, representative of the phylum Cnidaria polyp and medusa, names for the two body forms, one nonmotile and one typically free swimming, found ...

dome

(Encyclopedia)CE5 Parts of a dome dome, a roof circular or (rarely) elliptical in plan and usually hemispherical in form, placed over a circular, square, oblong, or polygonal space. Domes have been built with a...

electrolysis

(Encyclopedia)CE5 Electrolysis: In a typical reaction electrodes are placed in a solution of hydrogen chloride, HCl, which contains both hydrogen and chlorine ions. The battery removes electrons from the anode, ...

Kepler's laws

(Encyclopedia)CE5 Schematic representation of Kepler's second law: The areas ABF and A′B′F′ are equal and are swept out in equal intervals of time by a planet orbiting around the sun (at F). Kepler's laws...

Kievan Rus

(Encyclopedia)CE5 Kievan Rus (c.1000) Kievan Rus kēˈĕfən [key], medieval state of the Eastern Slavs. It was the earliest predecessor of modern Ukraine and Russia. Flourishing from the 10th to the 13th cent....

spurge

(Encyclopedia)CE5 Snow-on-the-mountain, Euphorbia marginata spurge spûrj [key], common name for members of the Euphorbiaceae, a family of herbs, shrubs, and trees of greatly varied structure and almost cosmopo...

benzene

(Encyclopedia)benzene bĕnˈzēn, bĕnzēnˈ [key], colorless, flammable, toxic liquid with a pleasant aromatic odor. It boils at 80.1℃ and solidifies at 5.5℃. Benzene is a hydrocarbon, with formula C6H6. The s...

weights and measures

(Encyclopedia)CE5 weights and measures, units and standards for expressing the amount of some quantity, such as length, capacity, or weight; the science of measurement standards and methods is known as metrology...