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radio-frequency identification

(Encyclopedia)radio-frequency identification (RFID), a technology that uses radio waves to transmit data and uniquely identify an animal, person, or thing. An RFID system typically consists of a tag and a reader. T...

metamorphism

(Encyclopedia)metamorphism, in geology, process of change in the structure, texture, or composition of rocks caused by agents of heat, deforming pressure, shearing stress, hot, chemically active fluids, or a combin...

Bakelite

(Encyclopedia)Bakelite bāˈkəlīt [key] [for its inventor, L. H. Baekeland], synthetic thermosetting resin. It has been widely used both alone, to form whole objects, and in combination with other materials, as a...

Dalton's law

(Encyclopedia)Dalton's law [for John Dalton], physical law that states that the total pressure exerted by a homogeneous mixture of gases is equal to the sum of the partial pressures of the individual gases. The par...

hardening

(Encyclopedia)hardening, in metallurgy, treatment of metals to increase their resistance to penetration. A metal is harder when it has small grains, which result when the metal is cooled rapidly. Sometimes small ar...

Bourdon gauge

(Encyclopedia)Bourdon gauge: see pressure.

language

(Encyclopedia)language, systematic communication by vocal symbols. It is a universal characteristic of the human species. Nothing is known of its origin, although scientists have identified a gene that clearly cont...

turbine

(Encyclopedia)CE5 Types of turbines turbine, rotary engine that uses a continuous stream of fluid (gas or liquid) to turn a shaft that can drive machinery. A water, or hydraulic, turbine is used to drive electr...

liquid crystal

(Encyclopedia)liquid crystal, liquid whose component particles, atoms or molecules, tend to arrange themselves with a degree of order far exceeding that found in ordinary liquids and approaching that of solid cryst...

air lock

(Encyclopedia)air lock, compartment connecting two different environments, usually at different pressures, that enables personnel to transfer from one environment to the other. Space capsules have air locks to enab...