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dielectric

(Encyclopedia)dielectric dīˌĭlĕkˈtrĭk [key], material that does not conduct electricity readily, i.e., an insulator (see insulation). A good dielectric should also have other properties: It must resist breakd...

citric acid

(Encyclopedia)citric acid or 2-hydroxy-1,2,3-propanetricarboxylic acid, HO2CCH2C(OH)(CO2H)CH2CO2H, an organic carboxylic acid containing three carboxyl groups; it is a solid at room temperature, melts at 153℃, an...

holmium

(Encyclopedia)holmium hōlˈmēəm [key] [Lat.,=Stockholm], metallic chemical element; symbol Ho; at. no. 67; at. wt. 164.93032; m.p. about 1,474℃; b.p. about 2,425℃; sp. gr. 8.78 at 25℃; valence +3. Holmium ...

jet stream

(Encyclopedia)jet stream, narrow, swift currents or tubes of air found at heights ranging from 7 to 8 mi (11.3–12.9 km) above the surface of the earth. They are caused by great temperature differences between adj...

saturated fat

(Encyclopedia)saturated fat, any solid fat that is an ester of glycerol and a saturated fatty acid. The molecules of a saturated fat have only single bonds between carbon atoms; if double bonds are present in the f...

silver chloride

(Encyclopedia)silver chloride, chemical compound, AgCl, a white cubic crystalline solid. It is nearly insoluble in water but is soluble in a water solution of ammonia, potassium cyanide, or sodium thiosulfate (“h...

Polke, Sigmar

(Encyclopedia)Polke, Sigmar, 1941–2011, innovative German artist best known for his paintings and photography. His family immigrated from East to West Germany in 1953, and he lived in Düsseldorf, studying (1961...

pineal gland

(Encyclopedia)pineal gland pĭnˈeəl [key], small organ (about the size of a pea) situated in the brain. Long considered vestigial in humans, the structure, which is also called the pineal body or the epiphysis, i...

nose

(Encyclopedia)nose, olfactory and respiratory organ, located between the eyes. The external nose, composed of bone and cartilage, is the most prominent feature of the face in humans. The internal nose is a hollow s...

emotion

(Encyclopedia)emotion, term commonly and loosely used to denote individual, subjective feelings which dictate moods. In psychology, emotion is considered a response to stimuli that involves characteristic physiolog...
 

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