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microelectronics

(Encyclopedia)microelectronics, branch of electronic technology devoted to the design and development of extremely small electronic devices that consume very little electric power. Although the term is sometimes us...

trypsin

(Encyclopedia)trypsin, enzyme that acts to degrade protein; it is often referred to as a proteolytic enzyme, or proteinase. Trypsin is one of the three principal digestive proteinases, the other two being pepsin an...

parity

(Encyclopedia)parity or space parity, in physics, quantity that refers to the relationship between an object or process and the image that it can produce in a mirror. For example, any right-handed object will produ...

fuel cell

(Encyclopedia)fuel cell, electric cell in which the chemical energy from the oxidation of a gas fuel is converted directly to electrical energy in a continuous process (see oxidation and reduction). The efficiency ...

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...

nucleosynthesis

(Encyclopedia)nucleosynthesis or nucleogenesis, in astronomy, production of all the chemical elements from the simplest element, hydrogen, by thermonuclear reactions within stars, supernovas, and in the big bang at...

Lippman, Gabriel Jonas

(Encyclopedia)Lippman, Gabriel Jonas, 1845–1921, French physicist, Ph.D. Sorbonne, 1875. He was a professor at the Sorbonne from 1883 until his death in 1921. Lippman received the 1908 Nobel Prize in Physics for ...

Michel, Hartmut

(Encyclopedia)Michel, Hartmut mĭkhˈəl [key], 1948–, German biochemist, Ph.D. Univ. of Würzburg, 1977. Michel was the first person to reduce a photosynthetic action center, which is a four-protein complex, to ...

Attica

(Encyclopedia)Attica ătˈĭkə [key], region of ancient Greece, a triangular area at the eastern end of central Greece, around Athens. According to Greek legend, the four Attic tribes were founded by Ion; in later...

legitimation

(Encyclopedia)legitimation, act of giving the status of legitimacy to a child whose parents were not married at the time the child was born. This is generally accomplished by the subsequent marriage of the parents....