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absorption

(Encyclopedia)absorption [Lat.,=sucking from], taking of molecules of one substance directly into another substance. It is contrasted with adsorption, in which the molecules adhere only to the surface of the second...

molecular modeling

(Encyclopedia)molecular modeling, the computer simulation, by various means, of chemical structures or processes. Special computer-graphics programs can display three-dimensional images of molecular structures and ...

geochemistry

(Encyclopedia)geochemistry, study of the chemical changes on the earth. More specifically, it is the study of the absolute and relative abundances of chemical elements in the minerals, soils, ores, rocks, water, an...

Leuna

(Encyclopedia)Leuna loiˈnä [key], city (1994 pop. 8,130), Saxony-Anhalt, S central Germany. There, in 1916, the first synthetic nitrogen plant began to operate after the invention of the Haber process. The city w...

Bergman, Torbern Olof

(Encyclopedia)Bergman, Torbern Olof to͝orˈbərn o͞oˈlôv bĕrˈyəmän [key], 1735–84, Swedish chemist, physicist, and mineralogist. A professor at the Univ. of Uppsala from 1758, he developed a theory of che...

Calvin, Melvin

(Encyclopedia)Calvin, Melvin, 1911–97, American organic chemist and educator, b. St. Paul, Minn., grad. Michigan College of Mining and Technology, 1931, Ph.D. Univ. of Minnesota, 1935. In 1937 he joined the facul...

Cornforth, Sir John Warcup

(Encyclopedia)Cornforth, Sir John Warcup wôrˈkəp côrnˈfərth [key], 1917–2013, Australian chemist, Ph.D. Oxford, 1941. Although Cornforth suffered a hearing loss from childhood and was deaf by the time he gr...

Henry's law

(Encyclopedia)Henry's law, chemical law stating that the amount of a gas that dissolves in a liquid is proportional to the partial pressure of the gas over the liquid, provided no chemical reaction takes place betw...

Semyonov, Nikolay Nikolayevich

(Encyclopedia)Semyonov, Nikolay Nikolayevich, or Nikolai Nikolaevic Semenov, 1896–1986, Soviet physical chemist, Ph.D. Petrograd Univ., 1917. Semyonov was a professor at the Leningrad Physico-Technical Institute ...

International Union of Pure and Applied Chemistry

(Encyclopedia)International Union of Pure and Applied Chemistry (IUPAC), an international organization est. 1919 to advance the chemical sciences and contribute to the application of chemistry to the service of hum...