Columbia Encyclopedia

Search results

500 results found

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...

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...

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...

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...

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...

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 ...

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...

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...

Stein, William Howard

(Encyclopedia)Stein, William Howard, 1911–80, American biochemist, b. New York City, Ph.D. Columbia, 1937. Stein was a professor at the Rockefeller Institute for Medical Research (now Rockefeller Univ.) from 1937...