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concentration

(Encyclopedia)concentration, in chemistry, measure of the relative proportions of two or more quantities in a mixture. The concentration of a solute is very important in studying chemical reactions because it deter...

obesity

(Encyclopedia)obesity, condition resulting from excessive storage of fat in the body. Obesity is now usually defined using a formula known as the body mass index (BMI), in which weight (in kilograms) is divided by ...

scale, in weights and measures

(Encyclopedia)scale, in weights and measures, instruments for determining weight, generally for other than laboratory use. For the principles of operation of all weighing devices, see balance. Platform scales utili...

atomic force microscope

(Encyclopedia)atomic force microscope (AFM), device that uses a spring-mounted probe to image individual atoms on the surface of a material, first developed by Gerd Binnig in 1986. Unlike the scanning tunneling mic...

atomic mass unit

(Encyclopedia)atomic mass unit or amu, in chemistry and physics, unit defined as exactly 1⁄12 the mass of an atom of carbon-12, the isotope of carbon with six protons and six neutrons in its nucleus. One amu is e...

specific gravity

(Encyclopedia)specific gravity, ratio of the weight of a given volume of a substance to the weight of an equal volume of some reference substance, or, equivalently, the ratio of the masses of equal volumes of the t...

Hofstadter, Robert

(Encyclopedia)Hofstadter, Robert, 1915–90, American physicist, b. New York City, Ph.D. Princeton, 1938. He taught at Princeton from 1938 to 1950 and also worked at the National Bureau of Standards during World Wa...

Blackett, Patrick Maynard Stuart

(Encyclopedia)Blackett, Patrick Maynard Stuart blăkˈĭt [key], 1897–1974, English physicist. He was professor of physics at the Univ. of Manchester (1937–53) and in 1953 became professor at the Univ. of Londo...

McNaughton, Andrew George Latta

(Encyclopedia)McNaughton, Andrew George Latta məknôtˈən [key], 1887–1966, Canadian general, b. Saskatchewan. An artillery officer in World War I, he was later (1929–35) Canadian chief of staff. In World War...

Rainwater, James

(Encyclopedia)Rainwater, James, 1917–86, American physicist, Ph.D. Columbia, 1946. After working on the Manhattan Project as a student during World War II, he became a professor of physics at Columbia in 1952. Hi...
 

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