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inclined plane

(Encyclopedia)CE5 Inclined plane inclined plane, simple machine, consisting of a sloping surface, whose purpose is to reduce the force that must be applied to raise a load. To raise a body vertically a force mu...

multiplication

(Encyclopedia)multiplication, fundamental operation in arithmetic and algebra. Multiplication by a whole number can be interpreted as successive addition. For example, a number N multiplied by 3 is N + N + N. In ge...

dispersion, in chemistry

(Encyclopedia)dispersion, in chemistry, mixture in which fine particles of one substance are scattered throughout another substance. A dispersion is classed as a suspension, colloid, or solution. Generally, the par...

Hofmann, August Wilhelm von

(Encyclopedia)Hofmann, August Wilhelm von ouˈgo͝ost vĭlˈhĕlm fən hôfˈmän [key], 1818–92, German organic chemist. He was professor at the Univ. of Berlin from 1865 and was a founder (1868) of the German C...

Kornberg, Roger David

(Encyclopedia)Kornberg, Roger David, 1947–, American biochemist, b. St. Louis, Mo., Ph.D. Stanford, 1972; son of Arthur Kornberg. Kornberg held academic posts at Cambridge (1972–76) and Harvard (1976–78) befo...

Prelog, Vladimir

(Encyclopedia)Prelog, Vladimir vlädyēˈmĭr prāˈlôg [key], 1906–98, Swiss chemist, b. Sarejevo, Austria-Hungary (now in Bosnia and Herzegovina). Educated in Prague, he worked in Yugoslavia until the German i...

radium

(Encyclopedia)radium rāˈdēəm [key] [Lat. radius=ray], radioactive metallic chemical element; symbol Ra; at. no. 88; mass number of most stable isotope 226; m.p. 700℃; b.p. 1,140℃; sp. gr. about 6.0; valence...

Mayweather, Floyd, Jr.

(Encyclopedia)Mayweather, Floyd, Jr., 1977–, American boxer, b. Grand Rapids, Mich., as Floyd Joy Sinclair. He began boxing at an early age, coached by his father, a welterweight boxer whose name he subsequently ...

Haworth, Sir Walter Norman

(Encyclopedia)Haworth, Sir Walter Norman, 1883–1950, British chemist, Ph.D. Univ. of Göttingen, 1911. Haworth held academic posts at Imperial College of Science and Technology in London (1911–12), the Univ. of...

Agre, Peter Courtland

(Encyclopedia)Agre, Peter Courtland, 1949–, American molecular biologist, b. Northfield, Minn., M.D. Johns Hopkins, 1974. From 1981 to 2005, Agre taught at Johns Hopkins in the departments of medicine and cell bi...