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semiconductor

(Encyclopedia)CE5 N-type and P-type crystals: In a pure silicon crystal each silicon atom (Si) is surrounded by four valence electrons. In the N-doped semiconductor, illustrated in the left-hand figure, some sil...

Sherman Antitrust Act

(Encyclopedia)Sherman Antitrust Act, 1890, first measure passed by the U.S. Congress to prohibit trusts; it was named for Senator John Sherman. Prior to its enactment, various states had passed similar laws, but th...

sickle cell disease

(Encyclopedia)sickle cell disease or sickle cell anemia, inherited disorder of the blood in which the oxygen-carrying hemoglobin pigment in erythrocytes (red blood cells) is abnormal. This “hemoglobin-S” crysta...

Royal Society

(Encyclopedia)Royal Society, oldest scientific organization in Great Britain and one of the oldest in Europe. It was founded in 1660 by a group of learned men in London who met to promote scientific discussion, par...

gay-rights movement

(Encyclopedia)gay-rights movement, organized efforts to end the criminalization of homosexuality and protect the civil rights of homosexuals. While there was some organized activity on behalf of the rights of homos...

war crimes

(Encyclopedia)war crimes, in international law, violations of the laws of war (see war, laws of). Those accused have been tried by their own military and civilian courts, by those of their enemy, and by expressly e...

pressure

(Encyclopedia)pressure, in mechanics, ratio of the force acting on a surface to the area of the surface; it is thus distinct from the total force acting on a surface. A force can be applied to and sustained by a si...

cardinal, in the Roman Catholic Church

(Encyclopedia)cardinal [Lat.,=attached to and thus “belonging to” the hinge], in the Roman Catholic Church, a member of the highest body of the church. The sacred college of cardinals of the Holy Roman Church i...

injunction

(Encyclopedia)injunction, in law, order of a court directing a party to perform a certain act or to refrain from an act or acts. The injunction, which developed as the main remedy in equity, is used especially wher...

Emancipation Proclamation

(Encyclopedia)Emancipation Proclamation, in U.S. history, the executive order abolishing slavery in the Confederate States of America. The proclamation did not reflect Lincoln's desired solution for the slavery p...

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