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Woodward, Robert Burns

(Encyclopedia)Woodward, Robert Burns, 1917–80, American chemist and educator, b. Boston, grad. Massachusetts Institute of Technology (S.B., 1936; Ph.D., 1937). He taught at Harvard from 1938, becoming Donner prof...

spring, in geology

(Encyclopedia)spring, in geology, natural flow of water from the ground or from rocks, representing an outlet for the water that has accumulated in permeable rock strata underground. Some of the water that falls as...

radiochemistry

(Encyclopedia)radiochemistry, chemistry of radioactive substances (see radioactivity). Radioactive isotopes are very useful as tracers to study the mechanisms of complex organic reactions, since even minute amounts...

ketone

(Encyclopedia)CE5 Ketones ketone kēˈtōn [key], any of a class of organic compounds that contain the carbonyl group, C=O, and in which the carbonyl group is bonded only to carbon atoms. The general formula fo...

winter cress

(Encyclopedia)winter cress or upland cress, species of Barbarea, herbs of the family Cruciferae (or Brassicaceae; mustard family). The pungent leaves of several species have been used for salads or garnishes, and t...

litmus

(Encyclopedia)litmus, organic dye usually used in the laboratory as an indicator of acidity or alkalinity (see acids and bases). Naturally pink in color, it turns blue in alkali solutions and red in acids. Commonly...

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 ...

deliquescence

(Encyclopedia)deliquescence dĕlˌəkwĕsˈəns [key], conversion of a solid substance into a liquid as a result of absorption of water vapor from the air. Since impurities in a solid lower its melting point, the a...

ammoniac

(Encyclopedia)ammoniac or gum ammoniac əmōˈnēăkˌ [key], yellowish substance with a sickening, bitter taste, obtained from the milky exudate of the injured stem of a plant (Dorema ammoniacum) found in Iran, In...

thymus gland

(Encyclopedia)thymus gland thīˈməs [key], mass of glandular tissue located in the neck or chest of most vertebrate animals. In humans, the thymus is a soft, flattened, pinkish-gray organ located in the upper che...